Association of genetic polymorphisms with erythrocyte traits: Verification of SNPs reported in a previous GWAS in a Japanese population

Erythrocyte count and volume are the commonly used hematological indices for anemia that change in various diseases. To date, however, only one study ever exists that addressed erythrocyte trait-associated single nucleotide polymorphisms (SNPs) in a Japanese population. Because that study was performed in patients with various diseases, we confirmed the reported associations in a general population. Participants in the current study were from the Shizuoka component of the Japan Multi-Institutional Collaborative Cohort Study, which included 4971 men and women aged 35 to 69 years who were recruited between 2006 and 2007. We analyzed the association of seven selected SNPs with the following erythrocyte traits: red blood cell count, hemoglobin (Hb) and hematocrit (Ht) levels, mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration. The erythrocyte traits were regressed on a number of minor alleles of selected SNPs. Then we compared our findings with those from a genome-wide association study performed in a Japanese population. We replicated the association of ABO rs495828, PDGFRA-KIT rs218237, USP49-MED20-BSYL-CCND3 rs3218097, C6orf182-CD164 rs11966072, TERT rs2736100, and TMPRSS6 rs5756504 with erythrocyte traits in our independent Japanese population. In addition, we found a significant interaction between TERT rs2736100 and smoking habit that affected Hb and Ht levels.