Distribution of human leukocyte antigens-E alleles in Thailand

The aim of this study was to investigate the distribution of human leukocyte antigens (HLA) -E alleles in Thailand. HLA-E alleles were assigned by using a polymerase chain reaction-sequence specific oligonucleotide probes (PCR-SSOP) method and direct sequencing in 200 healthy individuals. They comprised 100 Thai, 50 Chinese and 50 Thai-Chinese. From the results, three alleles of HLA-E could be detected in these populations. The E*0101 was the most common allele in Thai and Thai-Chinese with allelic frequencies of 42.5 per cent and 38 per cent, respectively. The other HLA-E allele frequencies of Thai origin were 33 per cent for E*01031 and 24.5 per cent for E*01032, respectively. Among Thai-Chinese, the allele frequencies of HLA-E were 31 per cent for E*01031 and E*01032, respectively. Whereas, the E*01031 was the predominant allele in Chinese origin with a frequency of 39 per cent, followed by E*0101 and E*01032 with 32 per cent and 29 per cent, respectively. No E*01033, E*0102 and E*0104 could be detected in all individuals. When comparing the distribution of HLA-E alleles between each of the populations (Thai vs Chinese, Thai vs Thai-Chinese and Chinese vs Thai-Chinese), no significant difference could be found among these populations. In addition, there was no significant difference of the distribution of HLA-E alleles between the study populations and other populations from Asian countries, reported previously. However, there were significant differences between the populations (Thai, Chinese and Thai-Chinese) and Danish (chi2 = 15.64, p = 0.0004; chi2 = 24.58, p = 0.0000046; chi2 = 14.69, p = 0.00065, respectively).