Multiethnic genome-wide association study of differentiated thyroid cancer in the EPITHYR consortium

Abstract

Incidence of differentiated thyroid carcinoma (DTC) varies considerably between ethnic groups, with particularly high incidence rates in Pacific Islanders. Here, we conducted a genome-wide association study (GWAS) involving 1,554 cases/1,973 controls of European ancestry and 301 cases/348 controls of Oceanian ancestry from the EPITHYR consortium. Our results confirmed the association with the known DTC susceptibility loci at 2q35, 8p12, 9q22.33 and 14q13.3 in the European ancestry population and suggested two novel signals at 1p31.3 (rs334729) and 16q23.2 (rs16950982), which were associated with TSH levels in previous GWAS. We additionally replicated an association with 5p15.33 reported previously in Chinese and European populations. Except at 1p31.3, all associations were in the same direction in the population of Oceanian ancestry. The frequencies of risk alleles at 2q35, 5p15.33 and 16q23.2 were significantly higher in Oceanians than in Europeans and may explain part of the highest DTC incidence observed in Oceanians.