Marie Lin

The genetic profile of Negritos of the Philippines differs from the non-Negrito groups with mitochondrial DNA haplogroups B4b1a2, B5, D6a, M, M52a, and N11b. Although Negritos are not seen in Taiwan, the strong genetic affinity between the Philippines and Taiwan Mountain Tribe Aborigines (TwMtA), and Folks tales of TwMtA, Saisiyat and Atayal recounting past contacts with Negritos, warrant the search for a Negrito signature in Taiwan. Material and Method: Discriminant Analysis of Principal Component (DAPC) was used to determine the genetic relationship between TwMtA, Filipino and non-TwMtA groups. Results: The deep coalescence of B4b1a2 in the Philippine Negritos, Saisiyat, Atayal, Island Southeast Asia, and SEA (Southeast Asia) suggested a deeply rooted common ancestry, but could not support a past Negrito presence in Taiwan. Conversely, the sharing of cultural components and mtDNA (mitochondrial DNA) haplogroup D6a2 in Saisiyat, Atayal and Philippine Negritos may characterize a Neg...

The human leukocyte antigen (HLA) system is widely used as a strategy in the search for the etiology of infectious diseases and autoimmune disorders. During the Taiwan epidemic of severe acute respiratory syndrome (SARS), many health care workers were infected. In an effort to establish a screening program for high risk personal, the distribution of HLA class I and II alleles in case and control groups was examined for the presence of an association to a genetic susceptibly or resistance to SARS coronavirus infection. HLA-class I and II allele typing by PCR-SSOP was performed on 37 cases of probable SARS, 28 fever patients excluded later as probable SARS, and 101 non-infected health care workers who were exposed or possibly exposed to SARS coronavirus. An additional control set of 190 normal healthy unrelated Taiwanese was also used in the analysis. Woolf and Haldane Odds ratio (OR) and corrected P-value (Pc) obtained from two tails Fisher exact test were used to show susceptibility...

To investigate the association of predisposing and protective HLA-DRB1 alleles with rheumatoid arthritis (RA) and its clinical markers in a Taiwanese population. A total of 273 patients with RA and 480 healthy controls, all of Taiwanese origin, were genotyped for HLA-DRB1 alleles by polymerase chain reaction and sequence-based typing assays. The associations between RA and HLA-DRB1 alleles and genotypes were investigated by chi-squared test. The DRB1*0405 and *1001 phenotypes showed the most significant associations with RA (OR 4.04, 95% CI 2.84-5.77, pc = 3.2 10(-14); OR 5.25, 95% CI 2.10-13.06, pc = 3.0 10(-3), respectively). Individuals carrying single or double doses of the shared epitope (SE/non-SE or SE/SE) had higher risks of RA. The compound heterozygote of DRB1*0405/*1001 showed the largest increase in RA risk (OR 15.8, 95% CI 2.48-100.7, pc = 0.004). Single or double doses of SE alleles were significantly associated with a higher bone erosion rate. Rheumatoid factor positi...

ABSTRACT The Jknull [Jk(a–b–)] phenotype, identified in Taiwanese populations during our previous investigation, 1 appears to have a relatively higher prevalence among indigenous Taiwanese persons. In this study, we analyzed the coding exon regions (Exons 4-11) of the JK gene of a Jknull Paiwan indigene to determine the molecular basis of the Jknull phe-notype in different Taiwanese populations. The Exon 4 to 11 region of the JK gene was divided into four segments, Exons 4 and 5, Exons 6 and 7, Exons 8 and 9, and Exons 10 and 11. Each segment was amplified by polymerase chain reaction (PCR) using specifically designed primer pairs (not shown) flanking for each specific exon region. Genomic DNA from the Jknull individual served as the tem-plate and the amplified DNA segment was then directly sequenced. The sequencing results demonstrated that each coding exon of the JK gene of this Jknull Paiwan indi-gene possessed the wild-type sequence, but was homozy-gous for a g>a mutation at the 3′ acceptor splice site of intron 5 (IVS5–1g>a) of the JK gene. Using PCR amplification and subsequent direct sequencing, we next analyzed the frequency of the JK IVS5–1g>a mutation among various Taiwanese population groups, including Taiwan's two major population groups, Minnan and Hakka, and the country's nine indigenous Austronesian-speaking groups. Because each individual has two JK alleles, we calculated allele frequencies by the formula "number of alleles identified/number of persons tested ¥ 2." The JK*IVS5–1g>a allele frequencies among Minnan and Hakka Taiwanese were 1.0 percent (1/50, number of alleles identified/number of persons tested) and 2.0 percent (2/50), respectively. The frequencies among the nine Taiwanese indigenous groups were as follow: Atayal 2.9 percent (3/52), Saisiat 1.0 percent (1/51), Tsou 0 percent (0/51), Bunun 3.0 percent (3/50), Paiwan 7.8 percent (8/51), Rukai 1.0 percent (1/50), Ami 4.8 percent (5/52), Puyuma 5.0 percent (5/50), and Yami 2.0 percent (2/49). Thus, the JK*IVS5–1g>a allele has been identified in every population group in Taiwan with the exception of the Tsou tribe. The frequency of the allele varies among the different population groups, most likely due to the historical isolation of the tribes and genetic drift, with the highest prevalence (7.8%) in the Paiwan tribe. We also analyzed the JK*IVS5–1g>a allele frequen-cies in three Southeast Asian populations, Fujian (south-east coast of China), Filipino, and Indonesian, which were 2.5 (3/61), 9.0 (9/50), and 1.0 (1/50), respectively. The Jk null phenotype is very rare in ethnic populations worldwide; however, it has been found to be relatively prevalent in Polynesian population groups with pheno-type frequencies of 0.1 to 1.4 percent. 2 The IVS5–1g>a mutation of the JK gene, first identified in a Jknull Chinese person, 3 is the main molecular basis for the Jknull pheno-type in Polynesian persons. A subsequent study demon-strated a frequency of 8.7 percent (8/46) for the JK*IVS5– 1g>a allele in this population. 4 Our previous investigations on human leukocyte antigens and the mitochondria DNA of Taiwanese indigenous groups demonstrated a relationship between indigenous Taiwanese and Polyne-sian populations. 5 The results of this study, which reveal a relatively high frequency of the JK*IVS5–1g>a allele in a number of Taiwanese indigenous groups, support the above hypothesis of a historical relationship between these ethnic groups.

BACKGROUND: In addition to the common ABO phenotypes, numerous phenotypes with a weak expression of the A or B antigens on RBCs have been found. This study describes the molecular genetic analysis of the Ael and the A3 phenotypes.STUDY DESIGN AND METHODS: The seven‐exon regions of the ABO genes of Ael and A3B individuals were amplified by PCR and cloned, and the sequences of the exons and their adjacent splice sites were analyzed. Samples from 30 randomly selected A1 individuals were also assessed.RESULTS: The A gene with wild‐type coding sequence was demonstrated in the Ael propositus, but all the six unrelated Taiwanese people with the Ael or AelB phenotype were shown to possess an A allele with the G→A mutation at the +5 position of intron 6 (IVS6+5G→A). RT‐PCR analysis showed that the complete A transcript structure was absent in the Ael RNA samples. The A3B individual possessed an A gene with an 838C→T missense mutation.CONCLUSION: The results suggest an association of the Ael*...

Background Yami and Ivatan islanders are Austronesian speakers from Orchid Island and the Batanes archipelago that are located between Taiwan and the Philippines. The paternal genealogies of the Yami tribe from 1962 monograph of Wei and Liu were compared with our dataset of non-recombining Y (NRY) chromosomes from the corresponding families. Then mitochondrial DNA polymorphism was also analyzed to determine the matrilineal relationships between Yami, Ivatan, and other East Asian populations. Results The family relationships inferred from the NRY Phylogeny suggested a low number of paternal founders and agreed with the genealogy of Wei and Liu (P < 0.01). Except for one Y short tandem repeat lineage (Y-STR), seen in two unrelated Yami families, no other Y-STR lineages were shared between villages, whereas mtDNA haplotypes were indiscriminately distributed throughout Orchid Island. The genetic affinity seen between Yami and Taiwanese aborigines or between Ivatan and the Philippine ...

The cell-surface straight and branched repeats of N-acetyllactosamine (LacNAc) units, called poly-LacNAc chains, characterize the histo-blood group i and I antigens, respectively. The transition of straight to branched poly-LacNAc chain (i to I) is determined by the I locus, which expresses 3 IGnT transcripts, IGnTA, IGnTB, and IGnTC. Our previous investigation demonstrated that the i-to-I transition in erythroid differentiation is regulated by the transcription factor CCAAT/enhancer binding protein α (C/EBPα). In the present investigation, the K-562 cell line was used as a model to show that the i-to-I transition is determined by the phosphorylation status of the C/EBPα Ser-21 residue, with dephosphorylated C/EBPα Ser-21 stimulating the transcription of the IGnTC gene, consequently resulting in I branching. Results from studies using adult erythropoietic and granulopoietic progenitor cells agreed with those derived using the K-562 cell model, with lentiviral expression of C/EBPα in...

The human i and I antigens are characterized as linear and branched repeats of N-acetyllactosamine, respectively. Conversion of the i to the I structure requires I-branching β-1,6-N-acetylglucosaminyltransferase activity. It has been noted that the null phenotype of I, the adult i phenotype, is associated with congenital cataracts in Asians. Previously, the identification of molecular changes in the IGnT gene, associated with the adult i phenotype, has been reported. In the present study, we demonstrate that the human I locus expresses 3 IGnT forms, designated IGnTA, IGnTB, and IGnTC, which have different exon 1, but identical exons 2 and 3, coding regions. The molecular genetics proposed for the I locus offer a new perspective on the formation and expression of the I antigen in different cells and provide insight into the questions derived from investigation of the adult i phenotype. Molecular genetic analyses of the Iloci of the 2 adult i groups, with and without congenital catara...