Genetic barriers in transplantation medicine.

The successful of transplantation is determined by the shared human leukocyte antigens (HLAs) and ABO blood group antigens between donor and recipient. In recent years, killer cell receptor [i.e., killer cell immunoglobulin-like receptor (KIR)] and major histocompatibility complex (MHC) class I chain-related gene molecule (i.e., MICA) were also reported as important determinants of transplant compatibility. At present, several different genotyping techniques (e.g., sequence specific primer and sequence based typing) can be used to characterize blood group, HLA, MICA and KIR and loci. These molecular techniques have several advantages because they do not depend on the availability of anti-sera, cellular expression and have greater specificity and accuracy compared with the antibody-antigen based typing. Nonetheless, these molecular techniques have limited capability to capture increasing number of markers which have been demonstrated to determine donor and recipient compatibility. It is now possible to genotype multiple markers and to the extent of a complete sequencing of the human genome using next generation sequencer (NGS). This high throughput genotyping platform has been tested for HLA, and it is expected that NGS will be used to simultaneously genotype a large number of clinically relevant transplantation genes in near future. This is not far from reality due to the bioinformatics support given by the immunogenetics community and the rigorous improvement in NGS methodology. In addition, new developments in immune tolerance based therapy, donor recruitment strategies and bioengineering are expected to provide significant advances in the field of transplantation medicine.

Distribution of cytokine gene polymorphisms in six Orang Asli subgroups in Peninsular Malaysia.

Cytokines are involved in immune responses and the pathogenesis of various diseases. Allelic variations within the genes coding for various ∼30 kDa cytokine protein/glycoproteins have been reported for many populations and have been the subjects of many ancestry and health analyses. In this study, we typed 22 single nucleotide polymorphisms (SNPs) in 13 cytokine genes of 165 Orang Asli individuals by using sequence specific primer-polymerase chain reaction (SSP-PCR) assay. The volunteers came from all across the Peninsular of Malaysia and belong to six Orang Asli subgroups; Batek, Kensiu, Lanoh, Che Wong, Semai and Orang Kanaq. Here we report our general findings and original genotype data and their associated analyses (Hardy-Weinberg proportions, estimation of allele and haplotype frequencies) can be found in the supplementary files and will be held at Allele Frequency Net Database (AFND).