Abd Razak, Tasnim
(2015)
Distribution of HLA alleles in the semang and senoi orang asli populations in Peninsular Malaysia.
Masters thesis, Universiti Sains Malaysia.
Abstract
Several waves of human migration into Peninsular Malaysia led to the stratification
of various ethnic groups. The earliest inhabitants of Peninsular Malaysia are the
Orang Asli population, namely Semang, Senoi and Proto Malay. In the present study,
we typed the HLA-A, -B and -DRB1 loci of the two oldest Orang Asli populations,
Semang and Senoi. Sequence-based HLA typing was performed on 85 individuals
from four Orang Asli subgroups: Kensiu (N = 21) and Bateq (N = 16) of the Semang
major group, and Che Wong (N = 10) and Semai (N = 38) of the Senoi major group.
A total of 11, 21 and 17 HLA-A, -B and -DRB1 alleles were identified, respectively
in the studied Orang Asli subgroups. HLA-A*02:01 was the most common allele in
Kensiu, Bateq and Che Wong, and A*24:07 was the most common in Semai.
B*18:01 was the most common allele in all of the Orang Asli subgroups.
DRB1*09:01 was the most common allele in Kensiu and Che Wong, and
DRBI*12:02 was the most common allele in Bateq and Semai. The following twoloci
haplotypes were common in the Orang Asli subgroups: HLA-A*02:01-B*18:01,
A*02:01-DRB1*09:01, A*02:01-DRB1*12:02, B*15:13-DRB1*12:02 and B*18:01-
DRB1*09:01. The three-loci, HLA-A*02:01-B*18:01-DRB1*09:01 haplotype was
observed in all the Orang Asli subgroups. The HLA analysis in this study suggested
that the Orang Asli subgroups experienced genetic drift based on evidence of limited
allelic diversity. Correspondence analysis based on HLA-A, -B and -DRB1 allele
frequencies suggested that the Orang Asli subgroups share high genetic affinity with
the populations from South China, Indochina, Malaysia, Singapore and Indonesia.
Although the HLA data is not conclusive to correlate the Semang with the African
population, there was one individual who expressed DRB1*15:03 allele in the
Kensiu where this allele is observed in high frequency in Africa. The Semang HLA
allelic characteristics showed similar profiles with those of other Southeast Asian
populations probably due to evolutionary pressure on the HLA gene complex. The
HLA data also demonstrated similar HLA allelic profiles of the Senoi with
Indochina/South China populations. In conclusion, HLA allelic profiles of the Orang
Asli subgroups can be said to be characteristically Southeast Asian. The
establishment of HLA database for selected Orang Asli subgroups may provide
useful reference in clinical applications (e.g. cell and organ transplants), HLAdisease
association studies, HLA-adverse drug reaction association studies and DNA
marker for personal identification and population genetics.
Actions (login required)
 |
View Item |
![[img]](http://eprints.usm.my/style/images/fileicons/application_pdf.png)
