Understanding the genetic history of Malay populations in Peninsular Malaysia via KIR genes diversity.

OBJECTIVES

Killer cell immunoglobulin-like receptor (KIR) genes with high polymorphism at genotypic levels are important in providing immune defense and have been expanded towards human population genetics. The aim of this study is to provide supporting information from this new biomarker to strengthen the comprehension of genetic history of the complex Malay population.

METHODS

KIR genotyping for 213 unadmixed Malay individuals from six subethnic groups (Acheh, Bugis, Champa, Mandailing, Minang and Kedah) was carried out using PCR-SSP (sequence specific primers) method in 16 independent reactions.

RESULTS

The most frequent KIR genotype observed is AA1, followed by AB4 and AB5. Five genotypes; AA1, AB4, AB5, AB7 and AB8 were shared among all Malay subethnic groups. The highest frequency of KIR haplotype A was observed in Minang Malays, whereas Acheh and Kedah Malays carry a balanced distribution of A and B KIR haplotypes. PCA for the KIR genes clearly illustrated six ethnogeographical population clusters; Africans, Amerindian, Northeast Asian, South Asian, Oceania and Southeast Asian populations. All six Malay subethnic groups fell within the Southeast Asian cluster.

CONCLUSIONS

The complex array of KIR genotypes observed in the Malays indicates their historical interactions with various populations, especially with the Chinese, Indians and Orang Asli. This study has demonstrated the potential of KIR genes as a genetic marker for deducing population structure and genetic relationship between populations.