METHODS: Two-hundred unrelated Emirati parents of patients selected for bone marrow transplantation were genotyped for HLA class I (A, B, C) and class II (DRB1, DQB1) genes using reverse sequence specific oligonucleotide bead-based multiplexing. HLA haplotypes were assigned with certainty by segregation (pedigree) analysis, and haplotype frequencies were obtained by direct counting. HLA class I and class II frequencies in Emiratis were compared to data from other populations using standard genetic distances (SGD), Neighbor-Joining (NJ) phylogenetic dendrograms, and correspondence analysis.
RESULTS: The studied HLA loci were in Hardy-Weinberg Equilibrium. We identified 17 HLA-A, 28 HLA-B, 14 HLA-C, 13 HLA-DRB1, and 5 HLA-DQB1 alleles, of which HLA-A*02 (22.2%), -B*51 (19.5%), -C*07 (20.0%), -DRB1*03 (22.2%), and -DQB1*02 (32.8%) were the most frequent allele lineages. DRB1*03~DQB1*02 (21.2%), DRB1*16~DQB1*05 (17.3%), B*35~C*04 (11.7%), B*08~DRB1*03 (9.7%), A*02~B*51 (7.5%), and A*26~C*07~B*08~DRB1*03~DQB1*02 (4.2%) were the most frequent two- and five-locus HLA haplotypes. Correspondence analysis and dendrograms showed that Emiratis were clustered with the Arabian Peninsula populations (Saudis, Omanis and Kuwaitis), West Mediterranean populations (North Africans, Iberians) and Pakistanis, but were distant from East Mediterranean (Turks, Albanians, Greek), Levantine (Syrians, Palestinians, Lebanese), Iranian, Iraqi Kurdish, and Sub-Saharan populations.
CONCLUSIONS: Emiratis were closely related to Arabian Peninsula populations, West Mediterranean populations and Pakistanis. However, the contribution of East Mediterranean, Levantine Arab, Iranian, and Sub-Saharan populations to the Emiratis' gene pool appears to be minor.
METHODS: Articles that report genetic polymorphisms, genotype frequencies and allele frequencies in CYP2C9, CYP2C19, CYP2D6 and CYP3A5 were retrieved from the PubMed database.
RESULTS AND DISCUSSIONS: A total of 86 studies that fulfilled the eligibility criteria representing different ethnic populations of SEEA, ie, Burmese, Chinese, Japanese, Karen ethnic minority, Korean, Malaysian, Philippino, Singaporean, Taiwanese, Thai, Indonesian, and Vietnamese, were included in the analysis. In general, the genotype frequencies across SEEA populations are comparable. The CYP2C9*1/*1 (69.3%-99.1%), *1/*3 (2.3%-20.1%) and *3/*3 (0%-2.2%) genotypes are reported in most SEEA populations. Six major CYP2C19 genotypes, ie, *1/*1 (6.25%-88.07%), *1/*2 (21.5%-86.46%), *1/*3 (0.8%-15.8%), *2/*2 (3.4%-14.5%), *2/*3 (0%-7.3%) and *3/*3 (0%-10.2%), are reported in most SEEA populations. Major CYP2D6 genotypes include *10/*10 (0%-69.6%), *1/*1 (0%-61.21%) and *1/*10 (0%-62.0%). Major CYP3A5 genotypes are *3/*3 (2.0%-71.4%), *1/*3 (16.0%-57.1%) and *1/*1 (0%-82.0%). Genotyping of abnormal genotypes of CYP2C9 (*1/*3), CYP2C19 (*1/*2, *1/*3), CYP3A5 (*1/*3) and CYP2D6 (*5/*10) associated with IM (Intermediate metabolizer) status, may be clinically beneficial in SEEA populations. Similarly, with CYP2C19 (*2/*2, *2/*3), CYP2D6 (*5/*5 ) linked to PM (Poor metabolizer), CYP2D6 (*10/*10, *1/*5 and to lesser extent *1/*4, *2/*5, *10/*41, *10/*49, *10/*14) and CYP3A5 (*1/*1) associated with EM (extensive metabolizer).
WHAT IS NEW AND CONCLUSION: Sufficient number of studies has provided comparable results in general. This review suggests that comparable genotype frequencies of CYP2C9, CYP2C19, CYP2D6 and CYP3A5 exist among the SEEA populations. It is noted that more research data are reported from East Asians compared with South-East Asians. Concerned efforts are required to establish partnerships among SEEA countries that will ensure sufficient data from South-East Asian countries which will assist in establishing the databases for SEEA populations.
METHODS: A total of 222 blood samples were collected from healthy, unrelated Malay, Chinese and Indian individuals. Their HNA-1, -3 and -4 and HNA-5 loci were genotyped using polymerase chain reaction-sequence specific primer (PCR-SSP) or PCR-restriction fragment length polymorphism (RFLP) assays.
RESULTS: All HNA loci are polymorphic, except for HNA -4. Geneotypes HNA-1a/1b, -3a/3b and -4a/4a were observed most frequently at these three loci in all three ethnic groups. In contrast, HNA-5a/5b and -5a/5a were observed as the predominant genotypes in Malays vs. Chinese and Indians, respectively. The Malays, Chinese and Indians shared HNA -3a (0.505-0.527), HNA -4a (1.000) and -5a (0.676-0.854) as the most frequent alleles. However, HNA-1a was found to be the most common in Malays (0.506) and Chinese (0.504) and HNA-1b for Indians (0.525).
CONCLUSION: Combined with HNA data that have been published for Malay subethnic and Orang Asli groups, this study provides the first fully comprehensive HNA dataset for populations to be found in Peninsular Malaysia. Overall, our findings provide further evidence of genetic complexity in the region. This now publicly available HNA dataset can be used as a reliable reference source for improving medical outcomes.