An indel introduced by Neanderthal introgression, rs3835124:ATTTATT > ATT, might contribute to prostate cancer risk by regulating PDK1 expression.

ABSTRACT

INTRODUCTION: Prostate cancer is one of the most common cancer types in males and rs12621278A > G has been suggested to be associated with this disease by previous genome-wide association studies. One thousand genomes project data analysis indicated that rs12621278A > G is within two long-core haplotypes. However, the origin, causal variant(s), and molecular function of these haplotypes were remaining unclear. MATERIALS AND METHODS: Population genetics analysis and functional genomics work was performed for this locus. RESULTS: Phylogeny analysis verified that the rare haplotype is derived from Neanderthal introgression. Genome annotation suggested that three genetic variants in the core haplotypes, rs116108611G > A, rs139972066AAAAAAAA > AAAAAAAAA, and rs3835124ATTTATT > ATT, are located in functional regions. Luciferase assay indicated that rs139972066AAAAAAAA > AAAAAAAAA and rs116108611G > A are not able to alter ITGA6 (integrin alpha 6) and ITGA6 antisense RNA 1 expression, respectively. In contrast, rs3835124ATTTATT > ATT can significantly influence PDK1 (pyruvate dehydrogenase kinase 1) expression, which was verified by expression quantitative trait locus analysis. This genetic variant can alter transcription factor cut like homeobox 1 interaction efficiency. The introgressed haplotype was observed to be subject to positive selection in East Asian populations. The molecular function of the haplotype suggested that Neanderthal should be with lower PDK1 expression and further different energy homeostasis from modern human. CONCLUSION: This study provided new insight into the contribution of Neanderthal introgression to human phenotypes.