Distribution of QPY and RAH haplotypes of granzyme B gene in distinct Brazilian populations

Revista da Sociedade Brasileira de Medicina Tropical

Fundação Hemominas, Uberaba¹  Instituto de Pesquisas em Patologias Tropicais de Rondônia, Porto Velho¹  Universidade de São Paulo, Ribeirão Preto¹  Garcia, Fernanda Bernadelli¹  Kashima, Simone¹  Moraes-Souza, Helio¹  Rodrigues, Evandra Strazza¹  Silva, Israel Tojal¹  Universidade Federal do Triângulo Mineiro, Uberaba¹  Covas, Dimas Tadeu¹  Malta, Tathiane Maistro¹  Nicolete, Larissa Deadame de Figueiredo¹ 

关键词: Granzyme B;    SNP;    QPY haplotype;    RAH haplotype;    Brazilian population;    Population distribution;   

DOI  :  10.1590/S0037-86822012005000001

学科分类：农业科学（综合）

来源: Sociedade Brasileira de Medicina Tropical

【 摘 要 】

INTRODUCTION: The cytolysis mediated by granules is one of the most important effector functions of cytotoxic T lymphocytes and natural killer cells. Recently, three single nucleotide polymorphisms (SNPs) were identified at exons 2, 3, and 5 of the granzyme B gene, resulting in a haplotype in which three amino acids of mature protein Q48P88Y245 are changed to R48A88H245, which leads to loss of cytotoxic activity of the protein. In this study, we evaluated the frequency of these polymorphisms in Brazilian populations.METHODS: We evaluated the frequency of these polymorphisms in Brazilian ethnic groups (white, Afro-Brazilian, and Asian) by sequencing these regions.RESULTS: The allelic and genotypic frequencies of SNP 2364A/G at exon 2 in Afro-Brazilian individuals (42.3% and 17.3%) were significantly higher when compared with those in whites and Asians (p < 0.0001 and p = 0.0007, respectively). The polymorphisms 2933C/G and 4243C/T also were more frequent in Afro-Brazilians but without any significant difference regarding the other groups. The Afro-Brazilian group presented greater diversity of haplotypes, and the RAH haplotype seemed to be more frequent in this group (25%), followed by the whites (20.7%) and by the Asians (11.9%), similar to the frequency presented in the literature.CONCLUSIONS: There is a higher frequency of polymorphisms in Afro-Brazilians, and the RAH haplotype was more frequent in these individuals. We believe that further studies should aim to investigate the correlation of this haplotype with diseases related to immunity mediated by cytotoxic lymphocytes, and if this correlation is confirmed, novel treatment strategies might be elaborated.

【 授权许可】

Unknown