Introduction: Pompe disease, a lysosomal storage disorder, is characterized by acid a-glucosidase... more Introduction: Pompe disease, a lysosomal storage disorder, is characterized by acid a-glucosidase (GAA) deficiency and categorized into two main subtypes: infantile-onset Pompe disease (IOPD) and late-onset Pompe disease (LOPD). The primary treatment, enzyme replacement therapy (ERT) with recombinant human GAA (rhGAA), faces challenges due to immunogenic responses, including the production of anti-drug antibody (ADA), which can diminish therapeutic efficacy. This study aims to assess the effectiveness of immune tolerance induction (ITI) therapy in cross-reactive immunologic material (CRIM)-positive Pompe disease patients with established high ADA levels. Method: In a single-center, open-label prospective study, we assessed ITI therapy's efficacy in Pompe disease patients, both IOPD and LOPD, with persistently elevated ADA titers (≥1:12,800) and clinical decline. The ITI regimen comprised bortezomib, rituximab, methotrexate, and intravenous immunoglobulin. Biochemical data, biomarkers, ADA titers, immune status, and respiratory and motor function were monitored over six months before and after ITI.
Background Duchenne muscular dystrophy (DMD/Duchenne) is a progressive X-linked muscular disease ... more Background Duchenne muscular dystrophy (DMD/Duchenne) is a progressive X-linked muscular disease with an overall incidence of 1:5,000 live male births. Recent availability in treatment for DMD raised the need of early diagnosis, and DMD became as a selective item of newborn screening (NBS) since Feb. 2021 in our center. Materials and methods Dried blood spots (DBS) muscle-type creatine kinase (CK) isoform was measured with a commercialized kit with age-adjusted cutoffs. Subjects with an elevation of CK in the first screen were requested for a re-screen 2 weeks later. A DBS whole-exome sequencing (WES) panel for dystrophin and other neuromuscular-related genes was applied to confirm the diagnosis for subjects with persistent hyperCKemia. Results During a 1-year period, 50,572 newborns (male 26,130) received DMD screening at a mean age of 2 days (SD 1 day). Among them, 632 (1.2%) had an elevated CK value. A re-screen at a mean age of 14 days (SD 8 days) revealed 14 subjects with persistent hyperCKemia, and DMD was confirmed in 3 of them. The incidence of DMD in Taiwan was 1:8,710 (95% CI 1 in 2,963 to 1 in 25,610) live birth males. Results of DMD DBS also assisted in Pompe newborn screening. Conclusions NBS for DMD enables earlier management of the disease. The high re-screening rate could potentially be waived by moving the DBS WES assay to a second-tier test. The long-term benefit and the impact of newborn screening on the prognosis of DMD, however, remain further elucidated. Duchenne muscular dystrophy (DMD) • Creatine kinase (CK) • Whole-exome sequencing (WES) • Newborn screening (NBS) * Yin-Hsiu Chien
Biotinidase deficiency is an autosomal recessive disorder that affects the endogenous recycling a... more Biotinidase deficiency is an autosomal recessive disorder that affects the endogenous recycling and release of biotin from dietary protein. This disease was thought to be rare in East Asia. In this report, we delineate the phenotype of biotinidase deficiency in our cohort. The genotypes and phenotypes of patients diagnosed with biotinidase deficiency from a medical center were reviewed. The clinical manifestations, laboratory findings, and molecular test results were retrospectively analyzed. A total of 6 patients were evaluated. Three patients (50%) were diagnosed because of a clinical illness, and the other three (50%) were identified by newborn screening. In all patients, the molecular results confirmed the BTD mutation. The three patients with clinical manifestations had an onset of seizure at the age of 2 to 3 months. Two patients had respiratory problems (one with apnea under bilevel positive airway pressure (BiPAP) therapy at night, and the other with laryngomalacia). Hearing loss and eye problems were found in one patient. Interestingly, cutaneous manifestations including skin eczema, alopecia, and recurrent fungal infection were less commonly seen compared to cases in the literature. None of the patients identified by the newborn screening program developed symptoms. Our findings highlight differences in the genotype and phenotype compared with those in Western countries. Patients with biotinidase deficiency benefit from newborn screening programs for early detection and management.
Multiple acyl-coenzyme A dehydrogenase deficiency (MADD) is a rare metabolic disorder with a dram... more Multiple acyl-coenzyme A dehydrogenase deficiency (MADD) is a rare metabolic disorder with a dramatic clinical presentation. It was recently discovered that MADD may present at an advanced age. The clinical and laboratory data of an index patient and patients previously diagnosed at our institution were collected. A systematic review of previous studies retrieved from the PubMed, MEDLINE, and Embase databases published by February 1, 2020 was performed to collect patients with very-late-onset MADD (VLO-MADD, onset age > 60 years) globally and patients with late-onset MADD (LO-MADD, onset age < 60 years) in Taiwan. The clinical characteristics of the VLO-MADD patients were compared to those of LO-MADD patients. We report a patient with VLO-MADD who developed the first symptom at the age of 61 years. The patient presented with a Reye-like syndrome after taking aspirin for coronary artery disease. Repeated bouts of weakness were noted. Two variants of c.250 G > A (;) 419C > T were observed in the ETFDH gene. Another four patients with VLO-MADD were identified globally. Eighteen patients with LO-MADD were collected from our department and previously reported patients in Taiwan. There was no difference in the clinical symptoms (except for the onset age) or laboratory data between these two groups. Homozygous variants were not observed in any patients in the VLO-MADD group but were detected in 12 patients (66.6%) in the LO-MADD group (p = 0.014). Patients with MADD may first show symptoms in their 6th decade or beyond. The disease course may lead to erroneous diagnoses in this age group.
Dementia frequently occurs in Down syndrome (DS) patients, and early intervention is important in... more Dementia frequently occurs in Down syndrome (DS) patients, and early intervention is important in its management. We have previously demonstrated a positive correlation of plasma βamyloids Aβ42 level and negative correlations of Aβ40 and tau levels with dementia in DS. In this study, we examined more cases and constructed composite scores with both tau and amyloids to correlated with dementia in DS. Plasma Aβ42, Aβ40, and tau proteins were measured by an immunomagnetic reduction assay in DS patients. Data were randomly and repeatedly split into training and validating sets, and logistic regression was applied to calculate area under curves (AUCs) for each biomarker. A total of 73 DS patients (among them 23 had neurodegeneration) and 77 controls were recruited. In DS patients without dementia, plasma Aβ40 and tau levels were highly elevated, but Aβ42 levels were lower than those of the healthy controls. DS patients with dementia, compared with DS patients with no dementia, had a large decline in Aβ40 and tau, but a rise in Aβ42. For biomarker scores correlating with dementia, Aβ40 revealed an AUC of 0.912; composite score Aβ40 × Tau revealed an AUC of 0.953; and a combined composite score of 0.1 Aβ40 × Tau + 0.9 Tau × Aβ40 / Aβ42 achieved the highest AUC of 0.965. Therefore, composite biomarker scores including both plasma tau and β-amyloids levels correlate with dementia in DS better than using individual biomarker scores. The pattern of tau decline and Aβ42 rise in DS patients with dementia are also different from previous findings in Alzheimer's disease.
Lysosomal storage diseases (LSDs) are a group of metabolic disorders resulting from a de ciency i... more Lysosomal storage diseases (LSDs) are a group of metabolic disorders resulting from a de ciency in one of the lysosomal hydrolases. Most LSDs are inherited in an autosomal or X-linked recessive manner. As LSDs are rare, their true incidence in Taiwan remains unknown. In this study, we used high-coverage WGS data from 1,495 Taiwanese individuals obtained from the Taiwan Biobank. We found 3,826 variants in 71 genes responsible for autosomal recessive LSDs. We rst excluded benign variants by allele frequency and other criteria. As a result, 270 variants were considered disease-causing. We curated these variants using published guidelines from the American College of Medical Genetics and Genomics (ACMG). Our results revealed a combined incidence rate of 13 per 100,000 (conservative estimation by pathologic and likely pathogenic variants; 95% CI 6.92-22.23) to94 per 100,000 (extended estimation by the inclusion of variants of unknown signi cance; 95% CI 75.96-115.03) among 71 autosomal recessive diseaseassociated genes. The conservative estimations were similar to those in published clinical data. No disease-causing mutations were found for 18 other diseases; thus, these diseases are likely extremely rare in Taiwan. The study results are important for designing screening and treatment methods for LSDs in Taiwan and demonstrate the importance of mutation curation to avoid overestimating disease incidences from genomic data.
Genetic epidemiological study doesn't support GLA IVS4+919G>A variant is a significant mutation i... more Genetic epidemiological study doesn't support GLA IVS4+919G>A variant is a significant mutation in Fabry disease. The address for the corresponding author was captured as affiliation for all authors. Please check if appropriate. Ymgme(2017),
International Journal of Neonatal Screening, Jun 23, 2017
A study of newborn screening for severe combined immunodeficiency (SCID) by detecting the T-cell ... more A study of newborn screening for severe combined immunodeficiency (SCID) by detecting the T-cell receptor excision circle (TRECs) copy number in dried blood spots (DBSs) collected from newborns 3 days of age began in 2010 in Taiwan, and SCID screening was subsequently implemented country-wide in 2012. A total of 920,398 newborns were screened during a period of 78 months. Of these, 175 newborns (0.02%) were requested to undergo an immune function survey, and 136 cases (1 in 6768 newborns) were ultimately diagnosed as having T cell lymphopenia. The screening detected seven cases of typical SCID, with an incidence of 1 in 131,485 newborns (95% confidence interval, 1/63,693~1/271,434). Hematopoietic stem cell transplantation was performed in six patients before overt infection occurred, and the survival rate was 100%. The screening also detected eight cases of SCID variants and 20 cases of 22q11.2 deletion syndrome. Other etiologies of T lymphopenia were identified, and those newborns were evaluated and managed according to their immunological status. Owing to the introduction of newborn screening by measuring the TREC copy number, early administration of treatments became possible for newborns with conditions that put them at risk of primary or secondary immunodeficiency.
Background: Whole-exome sequencing (WES) facilitates the diagnosis of hereditary neuromuscular di... more Background: Whole-exome sequencing (WES) facilitates the diagnosis of hereditary neuromuscular disorders. To achieve an accurate diagnosis, physicians should interpret the genetic report carefully along with clinical information and examinations. We described our experience with (1) clinical validation in patients with variants found using WES and (2) a diagnostic approach for those with negative findings from WES. Methods: WES was performed on patients with the clinical impression of hereditary neuromuscular disorders. Information on clinical manifestations, neurological examination, electrodiagnostic studies, histopathology of muscle and nerve, and laboratory tests were collected. Results: Forty-one patients (Male/Female: 18/23, age of onset: 34.5±15.9) accepted WES and were categorized into four scenarios: (1) patients with a positive WES result, (2) patients with an inconclusive WES result but supporting clinical data, (3) negative findings from WES, but a final diagnosis after ...
Hoyeraal-Hreidarsson syndrome (HHS) is the most severe form of dyskeratosis congenita (DC) and is... more Hoyeraal-Hreidarsson syndrome (HHS) is the most severe form of dyskeratosis congenita (DC) and is caused by mutations in genes involved in telomere maintenance. Here, we identified male siblings from a family with HHS carrying a hemizygous mutation (c.1345C > G, p.R449G), located in the C-terminal nuclear localization signal (NLS) of the DKC1 gene. These patients exhibit progressive cerebellar hypoplasia, recurrent infections, pancytopenia due to bone marrow failure, and short leukocyte telomere lengths. Single-cell RNA sequencing analysis suggested defects in the NLRP3 inflammasome in monocytes and the activation and maturation of NK cells and B cells. In experiments using induced pluripotent stem cells (iPSCs) from patients, DKC1_R449G iPSCs had short telomere lengths due to reduced levels of human telomerase RNA (hTR) and increased cytosolic proportions of DKC1. Treatment with dihydroquinolizinone RG7834 and 3′deoxyanosine cordycepin rescued telomere length in patient-derived iPSCs. Together, our findings not only provide new insights into immunodeficiency in DC patients but also provide treatment options for telomerase insufficiency disorders.
Background Gaucher disease (GD) is a lysosomal storage disorder characterized by deficient glucoc... more Background Gaucher disease (GD) is a lysosomal storage disorder characterized by deficient glucocerebrosidase activity that results from biallelic mutations in the GBA gene. Its phenotypic variability allows GD to be classified into 3 subtypes based on the presence and extent of neurological manifestations. Enzyme replacement therapy (ERT) has been available for all patients with GD in Taiwan since 1998. Newborn screening (NBS) for GD has been available since 2015. This study attempted to unveil the clinical features of patients diagnosed with GD at different eras in Taiwan. Materials and methods Data from the health records of two tertiary hospitals responsible for two-thirds of the patients with GD in Taiwan were used. The study population included all patients identified as having GD between 1998 and April 2022 in these two hospitals for review. A total of 42 individuals were included. Results Compared to that reported worldwide, our cohort presented a higher proportion of GD3 in...
Hoyeraal-Hreidarsson syndrome (HHS) is the most severe form of dyskeratosis congenita (DC) and is... more Hoyeraal-Hreidarsson syndrome (HHS) is the most severe form of dyskeratosis congenita (DC) and is caused by genes involved in telomere maintenance. Here, we identified male siblings from a family with HHS carrying a hemizygous mutation (c.1345C>G, p.R449G), located in the C-terminal nuclear localization signal (NLS) of the DKC1 gene. These patients exhibit progressive cerebellar hypoplasia, recurrent infections, pancytopenia due to bone marrow failure, and short leukocyte telomere lengths. Single-cell RNA sequencing analysis suggested defects in the NLRP3 inflammasome in monocytes and the activation and maturation of NK cells and B cells. In experiments using induced pluripotent stem cells (iPSCs) from patients, DKC1_R449G iPSCs had short telomere lengths due to reduced levels of human telomerase RNA (hTR) and increased cytosolic proportions of DKC1. Treatment with dihydroquinolizinone RG7834 and cordycepin rescued telomere length in patient-derived iPSCs. Together, our findings ...
BackgroundMucopolysaccharidoses (MPSs) are a group of inherited metabolic diseases, which are cha... more BackgroundMucopolysaccharidoses (MPSs) are a group of inherited metabolic diseases, which are characterized by the accumulation of glycosaminoglycans, and eventually lead to the progressive damage of various tissues and organs.MethodsAn epidemiological study of MPS in Taiwan was performed using multiple sources. The survival and diagnostic age for different types of MPS between 1985 and 2019 were evaluated.ResultsBetween 1985 and 2019, there were 175 patients diagnosed with MPS disorders in the Taiwanese population, with a median diagnostic age of 3.9 years. There were 21 (12%), 78 (45%), 33 (19%), 32 (18%) and 11 (6%) patients diagnosed with MPS I, II, III, IV and VI, respectively, with median diagnostic ages of 1.5, 3.8, 4.7, 4.5 and 3.7 years, respectively. Diagnosis of MPS patients was significantly earlier in recent decades (p<0.01). Pilot newborn screening programs for MPS I, II, VI, IVA, and IIIB were progressively introduced in Taiwan from 2016, and 48% (16/33) of MPS pat...
RASopathies are developmental diseases caused by mutations in rat sarcoma–mitogen‐activated prote... more RASopathies are developmental diseases caused by mutations in rat sarcoma–mitogen‐activated protein kinase pathway genes. These disorders, such as Noonan syndrome (NS) and NS‐related disorders (NSRD), including cardio‐facio‐cutaneous (CFC) syndrome, Costello syndrome (CS), and NS with multiple lentigines (NSML; also known as LEOPARD syndrome), have a similar systemic phenotype. A wide spectrum of congenital heart disease and hypertrophic cardiomyopathy (HCMP) can exhibit major associated characteristics. A retrospective study was conducted at the Mackay Memorial Hospital, National Taiwan University Hospital, Buddhist Tzu‐Chi General Hospital, Chang‐Gung Memorial Hospital, Taichung Veterans General Hospital, and Chung Shan Medical University Hospital from January 2007 to December 2018. We reviewed the clinical records of 76 patients with a confirmed molecular diagnosis of RASopathies, including NS, CS, CFC syndrome, and NSML. We evaluated the demographic data and medical records with...
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Identification of variants in the acid α-glucosidase (GAA) gene in Pompe disease provides valuabl... more Identification of variants in the acid α-glucosidase (GAA) gene in Pompe disease provides valuable insights and systematic overviews are needed. We report on the number, nature, frequency, and geographic distribution of GAA sequence variants listed in the Pompe Registry, a long-term, observational program and the largest global repository of Pompe disease data. Variant information was reviewed and compared with publicly available GAA databases/resources. Among 1,079 eligible patients, 2,075 GAA variants (80 unique novel) were reported. Variants were listed by groups representing Pompe disease phenotypes. Patients were classified as Group A: Symptom onset ≤ 12 months of age with cardiomyopathy; Group B: Symptom onset ≤ 12 years of age (includes patients with symptom onset ≤ 12 months of age without cardiomyopathy); or Group C: Symptom onset > 12 years of age. Likely impact of novel variants was predicted using bioinformatics algorithms. Variants were classified by pathogenicity using ACMG guidelines. Data reported from the Pompe Registry
Background: Most patients with isolated methylmalonic acidemia (MMA) /propionic acidemia (PA) pre... more Background: Most patients with isolated methylmalonic acidemia (MMA) /propionic acidemia (PA) presenting during the neonatal period with acute metabolic distress are at risk for death and significant neurodevelopmental disability. The nationwide newborn screening for MMA/PA has been in place in Taiwan from January, 2000 and data was collected until December, 2016. Results: During the study period, 3,155,263 newborns were screened. The overall incidence of MMA mutase type cases was 1/121,356 (n = 26), 1 cobalamin B was detected and that for PA cases (n = 4) was 1/788,816. The time of referral is 8.8 days for MMA patients, and 7.5 days for PA patients. The MMA mutase type patients have higher AST, ALT, and NH 3 values as well as a lower pH value (p < 0.05). The mean age for liver transplantation (LT) is 402 days (range from 0.6-6.7 yr) with 16 out of 20 cases (80.0%) using living donors. The mean admission length shortened from 90.6 days/year (pre-LT) to 5.3 days/year (at 3rd year post-LT) (p < 0.0005). Similarly, the tube feeding ratio decreased from 67.8 to 0.50% (p < 0.00005). The anxiety level of the caregiver was reduced from 33.4 to 27.2 after LT (p = 0.001) and the DQ/IQ performance of the patients was improved after LT from 50 to 60.1 (p = 0.07). Conclusion: MMA/PA patients with LT do survive and have reduced admission time, reduced tube feeding and the caregiver is less anxious.
Background/Aims: Fabry disease (FD), a rare x-lined genetic disorder is a cause of renal deterior... more Background/Aims: Fabry disease (FD), a rare x-lined genetic disorder is a cause of renal deterioration. The phenotype of FD is highly variable and nonspecific, and correct diagnosis has always been delayed. We aimed to explore the prevalence and clinical presentation of FD in this high-risk male population in a Northern Taiwan medical center. Methods: This is the first study to survey the incidence of FD in this high-risk population through the platform of a chronic kidney disease (CKD) education program in Asia. A total of 1,012 male patients with unknown CKD causes were screened using an assay of alpha-galactosidase A activity (α-Gal A) by dried blood spots (DBS). A final GLA gene analysis was also done for those with low enzyme activity. Results: We identified two new patients with classic FD and four patients with late-onset FD. One novel GLA mutation with c.413 G>A was found in one classic FD patient (index 5). The prevalence of FD is about 0.59 % (6 in 1,012) in the high-ri...
Introduction: Pompe disease, a lysosomal storage disorder, is characterized by acid a-glucosidase... more Introduction: Pompe disease, a lysosomal storage disorder, is characterized by acid a-glucosidase (GAA) deficiency and categorized into two main subtypes: infantile-onset Pompe disease (IOPD) and late-onset Pompe disease (LOPD). The primary treatment, enzyme replacement therapy (ERT) with recombinant human GAA (rhGAA), faces challenges due to immunogenic responses, including the production of anti-drug antibody (ADA), which can diminish therapeutic efficacy. This study aims to assess the effectiveness of immune tolerance induction (ITI) therapy in cross-reactive immunologic material (CRIM)-positive Pompe disease patients with established high ADA levels. Method: In a single-center, open-label prospective study, we assessed ITI therapy's efficacy in Pompe disease patients, both IOPD and LOPD, with persistently elevated ADA titers (≥1:12,800) and clinical decline. The ITI regimen comprised bortezomib, rituximab, methotrexate, and intravenous immunoglobulin. Biochemical data, biomarkers, ADA titers, immune status, and respiratory and motor function were monitored over six months before and after ITI.
Background Duchenne muscular dystrophy (DMD/Duchenne) is a progressive X-linked muscular disease ... more Background Duchenne muscular dystrophy (DMD/Duchenne) is a progressive X-linked muscular disease with an overall incidence of 1:5,000 live male births. Recent availability in treatment for DMD raised the need of early diagnosis, and DMD became as a selective item of newborn screening (NBS) since Feb. 2021 in our center. Materials and methods Dried blood spots (DBS) muscle-type creatine kinase (CK) isoform was measured with a commercialized kit with age-adjusted cutoffs. Subjects with an elevation of CK in the first screen were requested for a re-screen 2 weeks later. A DBS whole-exome sequencing (WES) panel for dystrophin and other neuromuscular-related genes was applied to confirm the diagnosis for subjects with persistent hyperCKemia. Results During a 1-year period, 50,572 newborns (male 26,130) received DMD screening at a mean age of 2 days (SD 1 day). Among them, 632 (1.2%) had an elevated CK value. A re-screen at a mean age of 14 days (SD 8 days) revealed 14 subjects with persistent hyperCKemia, and DMD was confirmed in 3 of them. The incidence of DMD in Taiwan was 1:8,710 (95% CI 1 in 2,963 to 1 in 25,610) live birth males. Results of DMD DBS also assisted in Pompe newborn screening. Conclusions NBS for DMD enables earlier management of the disease. The high re-screening rate could potentially be waived by moving the DBS WES assay to a second-tier test. The long-term benefit and the impact of newborn screening on the prognosis of DMD, however, remain further elucidated. Duchenne muscular dystrophy (DMD) • Creatine kinase (CK) • Whole-exome sequencing (WES) • Newborn screening (NBS) * Yin-Hsiu Chien
Biotinidase deficiency is an autosomal recessive disorder that affects the endogenous recycling a... more Biotinidase deficiency is an autosomal recessive disorder that affects the endogenous recycling and release of biotin from dietary protein. This disease was thought to be rare in East Asia. In this report, we delineate the phenotype of biotinidase deficiency in our cohort. The genotypes and phenotypes of patients diagnosed with biotinidase deficiency from a medical center were reviewed. The clinical manifestations, laboratory findings, and molecular test results were retrospectively analyzed. A total of 6 patients were evaluated. Three patients (50%) were diagnosed because of a clinical illness, and the other three (50%) were identified by newborn screening. In all patients, the molecular results confirmed the BTD mutation. The three patients with clinical manifestations had an onset of seizure at the age of 2 to 3 months. Two patients had respiratory problems (one with apnea under bilevel positive airway pressure (BiPAP) therapy at night, and the other with laryngomalacia). Hearing loss and eye problems were found in one patient. Interestingly, cutaneous manifestations including skin eczema, alopecia, and recurrent fungal infection were less commonly seen compared to cases in the literature. None of the patients identified by the newborn screening program developed symptoms. Our findings highlight differences in the genotype and phenotype compared with those in Western countries. Patients with biotinidase deficiency benefit from newborn screening programs for early detection and management.
Multiple acyl-coenzyme A dehydrogenase deficiency (MADD) is a rare metabolic disorder with a dram... more Multiple acyl-coenzyme A dehydrogenase deficiency (MADD) is a rare metabolic disorder with a dramatic clinical presentation. It was recently discovered that MADD may present at an advanced age. The clinical and laboratory data of an index patient and patients previously diagnosed at our institution were collected. A systematic review of previous studies retrieved from the PubMed, MEDLINE, and Embase databases published by February 1, 2020 was performed to collect patients with very-late-onset MADD (VLO-MADD, onset age > 60 years) globally and patients with late-onset MADD (LO-MADD, onset age < 60 years) in Taiwan. The clinical characteristics of the VLO-MADD patients were compared to those of LO-MADD patients. We report a patient with VLO-MADD who developed the first symptom at the age of 61 years. The patient presented with a Reye-like syndrome after taking aspirin for coronary artery disease. Repeated bouts of weakness were noted. Two variants of c.250 G > A (;) 419C > T were observed in the ETFDH gene. Another four patients with VLO-MADD were identified globally. Eighteen patients with LO-MADD were collected from our department and previously reported patients in Taiwan. There was no difference in the clinical symptoms (except for the onset age) or laboratory data between these two groups. Homozygous variants were not observed in any patients in the VLO-MADD group but were detected in 12 patients (66.6%) in the LO-MADD group (p = 0.014). Patients with MADD may first show symptoms in their 6th decade or beyond. The disease course may lead to erroneous diagnoses in this age group.
Dementia frequently occurs in Down syndrome (DS) patients, and early intervention is important in... more Dementia frequently occurs in Down syndrome (DS) patients, and early intervention is important in its management. We have previously demonstrated a positive correlation of plasma βamyloids Aβ42 level and negative correlations of Aβ40 and tau levels with dementia in DS. In this study, we examined more cases and constructed composite scores with both tau and amyloids to correlated with dementia in DS. Plasma Aβ42, Aβ40, and tau proteins were measured by an immunomagnetic reduction assay in DS patients. Data were randomly and repeatedly split into training and validating sets, and logistic regression was applied to calculate area under curves (AUCs) for each biomarker. A total of 73 DS patients (among them 23 had neurodegeneration) and 77 controls were recruited. In DS patients without dementia, plasma Aβ40 and tau levels were highly elevated, but Aβ42 levels were lower than those of the healthy controls. DS patients with dementia, compared with DS patients with no dementia, had a large decline in Aβ40 and tau, but a rise in Aβ42. For biomarker scores correlating with dementia, Aβ40 revealed an AUC of 0.912; composite score Aβ40 × Tau revealed an AUC of 0.953; and a combined composite score of 0.1 Aβ40 × Tau + 0.9 Tau × Aβ40 / Aβ42 achieved the highest AUC of 0.965. Therefore, composite biomarker scores including both plasma tau and β-amyloids levels correlate with dementia in DS better than using individual biomarker scores. The pattern of tau decline and Aβ42 rise in DS patients with dementia are also different from previous findings in Alzheimer's disease.
Lysosomal storage diseases (LSDs) are a group of metabolic disorders resulting from a de ciency i... more Lysosomal storage diseases (LSDs) are a group of metabolic disorders resulting from a de ciency in one of the lysosomal hydrolases. Most LSDs are inherited in an autosomal or X-linked recessive manner. As LSDs are rare, their true incidence in Taiwan remains unknown. In this study, we used high-coverage WGS data from 1,495 Taiwanese individuals obtained from the Taiwan Biobank. We found 3,826 variants in 71 genes responsible for autosomal recessive LSDs. We rst excluded benign variants by allele frequency and other criteria. As a result, 270 variants were considered disease-causing. We curated these variants using published guidelines from the American College of Medical Genetics and Genomics (ACMG). Our results revealed a combined incidence rate of 13 per 100,000 (conservative estimation by pathologic and likely pathogenic variants; 95% CI 6.92-22.23) to94 per 100,000 (extended estimation by the inclusion of variants of unknown signi cance; 95% CI 75.96-115.03) among 71 autosomal recessive diseaseassociated genes. The conservative estimations were similar to those in published clinical data. No disease-causing mutations were found for 18 other diseases; thus, these diseases are likely extremely rare in Taiwan. The study results are important for designing screening and treatment methods for LSDs in Taiwan and demonstrate the importance of mutation curation to avoid overestimating disease incidences from genomic data.
Genetic epidemiological study doesn't support GLA IVS4+919G>A variant is a significant mutation i... more Genetic epidemiological study doesn't support GLA IVS4+919G>A variant is a significant mutation in Fabry disease. The address for the corresponding author was captured as affiliation for all authors. Please check if appropriate. Ymgme(2017),
International Journal of Neonatal Screening, Jun 23, 2017
A study of newborn screening for severe combined immunodeficiency (SCID) by detecting the T-cell ... more A study of newborn screening for severe combined immunodeficiency (SCID) by detecting the T-cell receptor excision circle (TRECs) copy number in dried blood spots (DBSs) collected from newborns 3 days of age began in 2010 in Taiwan, and SCID screening was subsequently implemented country-wide in 2012. A total of 920,398 newborns were screened during a period of 78 months. Of these, 175 newborns (0.02%) were requested to undergo an immune function survey, and 136 cases (1 in 6768 newborns) were ultimately diagnosed as having T cell lymphopenia. The screening detected seven cases of typical SCID, with an incidence of 1 in 131,485 newborns (95% confidence interval, 1/63,693~1/271,434). Hematopoietic stem cell transplantation was performed in six patients before overt infection occurred, and the survival rate was 100%. The screening also detected eight cases of SCID variants and 20 cases of 22q11.2 deletion syndrome. Other etiologies of T lymphopenia were identified, and those newborns were evaluated and managed according to their immunological status. Owing to the introduction of newborn screening by measuring the TREC copy number, early administration of treatments became possible for newborns with conditions that put them at risk of primary or secondary immunodeficiency.
Background: Whole-exome sequencing (WES) facilitates the diagnosis of hereditary neuromuscular di... more Background: Whole-exome sequencing (WES) facilitates the diagnosis of hereditary neuromuscular disorders. To achieve an accurate diagnosis, physicians should interpret the genetic report carefully along with clinical information and examinations. We described our experience with (1) clinical validation in patients with variants found using WES and (2) a diagnostic approach for those with negative findings from WES. Methods: WES was performed on patients with the clinical impression of hereditary neuromuscular disorders. Information on clinical manifestations, neurological examination, electrodiagnostic studies, histopathology of muscle and nerve, and laboratory tests were collected. Results: Forty-one patients (Male/Female: 18/23, age of onset: 34.5±15.9) accepted WES and were categorized into four scenarios: (1) patients with a positive WES result, (2) patients with an inconclusive WES result but supporting clinical data, (3) negative findings from WES, but a final diagnosis after ...
Hoyeraal-Hreidarsson syndrome (HHS) is the most severe form of dyskeratosis congenita (DC) and is... more Hoyeraal-Hreidarsson syndrome (HHS) is the most severe form of dyskeratosis congenita (DC) and is caused by mutations in genes involved in telomere maintenance. Here, we identified male siblings from a family with HHS carrying a hemizygous mutation (c.1345C > G, p.R449G), located in the C-terminal nuclear localization signal (NLS) of the DKC1 gene. These patients exhibit progressive cerebellar hypoplasia, recurrent infections, pancytopenia due to bone marrow failure, and short leukocyte telomere lengths. Single-cell RNA sequencing analysis suggested defects in the NLRP3 inflammasome in monocytes and the activation and maturation of NK cells and B cells. In experiments using induced pluripotent stem cells (iPSCs) from patients, DKC1_R449G iPSCs had short telomere lengths due to reduced levels of human telomerase RNA (hTR) and increased cytosolic proportions of DKC1. Treatment with dihydroquinolizinone RG7834 and 3′deoxyanosine cordycepin rescued telomere length in patient-derived iPSCs. Together, our findings not only provide new insights into immunodeficiency in DC patients but also provide treatment options for telomerase insufficiency disorders.
Background Gaucher disease (GD) is a lysosomal storage disorder characterized by deficient glucoc... more Background Gaucher disease (GD) is a lysosomal storage disorder characterized by deficient glucocerebrosidase activity that results from biallelic mutations in the GBA gene. Its phenotypic variability allows GD to be classified into 3 subtypes based on the presence and extent of neurological manifestations. Enzyme replacement therapy (ERT) has been available for all patients with GD in Taiwan since 1998. Newborn screening (NBS) for GD has been available since 2015. This study attempted to unveil the clinical features of patients diagnosed with GD at different eras in Taiwan. Materials and methods Data from the health records of two tertiary hospitals responsible for two-thirds of the patients with GD in Taiwan were used. The study population included all patients identified as having GD between 1998 and April 2022 in these two hospitals for review. A total of 42 individuals were included. Results Compared to that reported worldwide, our cohort presented a higher proportion of GD3 in...
Hoyeraal-Hreidarsson syndrome (HHS) is the most severe form of dyskeratosis congenita (DC) and is... more Hoyeraal-Hreidarsson syndrome (HHS) is the most severe form of dyskeratosis congenita (DC) and is caused by genes involved in telomere maintenance. Here, we identified male siblings from a family with HHS carrying a hemizygous mutation (c.1345C>G, p.R449G), located in the C-terminal nuclear localization signal (NLS) of the DKC1 gene. These patients exhibit progressive cerebellar hypoplasia, recurrent infections, pancytopenia due to bone marrow failure, and short leukocyte telomere lengths. Single-cell RNA sequencing analysis suggested defects in the NLRP3 inflammasome in monocytes and the activation and maturation of NK cells and B cells. In experiments using induced pluripotent stem cells (iPSCs) from patients, DKC1_R449G iPSCs had short telomere lengths due to reduced levels of human telomerase RNA (hTR) and increased cytosolic proportions of DKC1. Treatment with dihydroquinolizinone RG7834 and cordycepin rescued telomere length in patient-derived iPSCs. Together, our findings ...
BackgroundMucopolysaccharidoses (MPSs) are a group of inherited metabolic diseases, which are cha... more BackgroundMucopolysaccharidoses (MPSs) are a group of inherited metabolic diseases, which are characterized by the accumulation of glycosaminoglycans, and eventually lead to the progressive damage of various tissues and organs.MethodsAn epidemiological study of MPS in Taiwan was performed using multiple sources. The survival and diagnostic age for different types of MPS between 1985 and 2019 were evaluated.ResultsBetween 1985 and 2019, there were 175 patients diagnosed with MPS disorders in the Taiwanese population, with a median diagnostic age of 3.9 years. There were 21 (12%), 78 (45%), 33 (19%), 32 (18%) and 11 (6%) patients diagnosed with MPS I, II, III, IV and VI, respectively, with median diagnostic ages of 1.5, 3.8, 4.7, 4.5 and 3.7 years, respectively. Diagnosis of MPS patients was significantly earlier in recent decades (p<0.01). Pilot newborn screening programs for MPS I, II, VI, IVA, and IIIB were progressively introduced in Taiwan from 2016, and 48% (16/33) of MPS pat...
RASopathies are developmental diseases caused by mutations in rat sarcoma–mitogen‐activated prote... more RASopathies are developmental diseases caused by mutations in rat sarcoma–mitogen‐activated protein kinase pathway genes. These disorders, such as Noonan syndrome (NS) and NS‐related disorders (NSRD), including cardio‐facio‐cutaneous (CFC) syndrome, Costello syndrome (CS), and NS with multiple lentigines (NSML; also known as LEOPARD syndrome), have a similar systemic phenotype. A wide spectrum of congenital heart disease and hypertrophic cardiomyopathy (HCMP) can exhibit major associated characteristics. A retrospective study was conducted at the Mackay Memorial Hospital, National Taiwan University Hospital, Buddhist Tzu‐Chi General Hospital, Chang‐Gung Memorial Hospital, Taichung Veterans General Hospital, and Chung Shan Medical University Hospital from January 2007 to December 2018. We reviewed the clinical records of 76 patients with a confirmed molecular diagnosis of RASopathies, including NS, CS, CFC syndrome, and NSML. We evaluated the demographic data and medical records with...
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Identification of variants in the acid α-glucosidase (GAA) gene in Pompe disease provides valuabl... more Identification of variants in the acid α-glucosidase (GAA) gene in Pompe disease provides valuable insights and systematic overviews are needed. We report on the number, nature, frequency, and geographic distribution of GAA sequence variants listed in the Pompe Registry, a long-term, observational program and the largest global repository of Pompe disease data. Variant information was reviewed and compared with publicly available GAA databases/resources. Among 1,079 eligible patients, 2,075 GAA variants (80 unique novel) were reported. Variants were listed by groups representing Pompe disease phenotypes. Patients were classified as Group A: Symptom onset ≤ 12 months of age with cardiomyopathy; Group B: Symptom onset ≤ 12 years of age (includes patients with symptom onset ≤ 12 months of age without cardiomyopathy); or Group C: Symptom onset > 12 years of age. Likely impact of novel variants was predicted using bioinformatics algorithms. Variants were classified by pathogenicity using ACMG guidelines. Data reported from the Pompe Registry
Background: Most patients with isolated methylmalonic acidemia (MMA) /propionic acidemia (PA) pre... more Background: Most patients with isolated methylmalonic acidemia (MMA) /propionic acidemia (PA) presenting during the neonatal period with acute metabolic distress are at risk for death and significant neurodevelopmental disability. The nationwide newborn screening for MMA/PA has been in place in Taiwan from January, 2000 and data was collected until December, 2016. Results: During the study period, 3,155,263 newborns were screened. The overall incidence of MMA mutase type cases was 1/121,356 (n = 26), 1 cobalamin B was detected and that for PA cases (n = 4) was 1/788,816. The time of referral is 8.8 days for MMA patients, and 7.5 days for PA patients. The MMA mutase type patients have higher AST, ALT, and NH 3 values as well as a lower pH value (p < 0.05). The mean age for liver transplantation (LT) is 402 days (range from 0.6-6.7 yr) with 16 out of 20 cases (80.0%) using living donors. The mean admission length shortened from 90.6 days/year (pre-LT) to 5.3 days/year (at 3rd year post-LT) (p < 0.0005). Similarly, the tube feeding ratio decreased from 67.8 to 0.50% (p < 0.00005). The anxiety level of the caregiver was reduced from 33.4 to 27.2 after LT (p = 0.001) and the DQ/IQ performance of the patients was improved after LT from 50 to 60.1 (p = 0.07). Conclusion: MMA/PA patients with LT do survive and have reduced admission time, reduced tube feeding and the caregiver is less anxious.
Background/Aims: Fabry disease (FD), a rare x-lined genetic disorder is a cause of renal deterior... more Background/Aims: Fabry disease (FD), a rare x-lined genetic disorder is a cause of renal deterioration. The phenotype of FD is highly variable and nonspecific, and correct diagnosis has always been delayed. We aimed to explore the prevalence and clinical presentation of FD in this high-risk male population in a Northern Taiwan medical center. Methods: This is the first study to survey the incidence of FD in this high-risk population through the platform of a chronic kidney disease (CKD) education program in Asia. A total of 1,012 male patients with unknown CKD causes were screened using an assay of alpha-galactosidase A activity (α-Gal A) by dried blood spots (DBS). A final GLA gene analysis was also done for those with low enzyme activity. Results: We identified two new patients with classic FD and four patients with late-onset FD. One novel GLA mutation with c.413 G>A was found in one classic FD patient (index 5). The prevalence of FD is about 0.59 % (6 in 1,012) in the high-ri...
Uploads
Papers by Yin-hsiu Chien