Different allelic frequencies of several cytokine genes in Hong Kong Chinese and Swedish Caucasians.

It has been shown that cytokine gene polymorphisms are important in the regulation of the level of cytokine production that may affect the development and extent of inflammatory diseases and transplant rejections. The frequency of the -308 TNFA, -383 TNFR1, -1087 IL10 and codon 25 TGFB1 alleles were analysed in two different ethnic groups: Chinese from Hong Kong and Caucasians from western Sweden. Significant differences in the occurrence of the analysed alleles were shown between the two populations. The most profound difference was found in the frequency of the A/A genotype at the -1087 position of IL10 gene (18% in Caucasians and 89% in Chinese, P < 0.0001, both for the genotype and allele frequencies) and less although statistically significant for other investigated genes. The noted differences in the frequency of functionally important alleles of cytokine genes may have consequences for the mode of appearance and outcome of certain diseases in individuals of different ethnicity.