Single Nucleotide Polymorphisms and Colorectal Cancer Risk: The First Replication Study in a South American Population

Abstract

Colorectal cancer (CRC) heritability is determined by the complex interaction between inherited variants and environmental factors. CRC incidence rates have been increasing specially in developing countries, such as Brazil, where CRC is the third most frequent cancer in both genders. Genome‐wide association studies (GWAS), based on thousands of cases and controls typed at thousands of single nucleotide polymorphisms (SNPs), have identiied several variants that associate with gastrointestinal cancer risk. Less of half of the familial risk has been elucidated through GWAS that identiied common SNPs in almost exclusively European populations. Replication studies in admixed heterogeneous populations are scarce and most failed to replicate all the imputed SNPs. Population stratiication by ethnic subgroups with diferent allele frequencies and so with difer‐ ent paterns of linkage disequilibrium may cause expurious associations. Here, we show the irst replication study of CRC inherited susceptibility in South America and aimed to identify known SNPs, which are associated with CRC risk in European populations.