For in silico replication, we selected the CYP2A6 locus, along with five genome-wide loci for CPD that had , in an additional independent sample of 5,462 Japanese subjects from the BioBank Japan Project (Table S1). We assessed the CPD association with the CNP (rs8102683) at the CYP2A6 locus and five representative SNPs for the other loci; only the CNP (rs8102683) at the CYP2A6 locus was significantly replicated (; Table S2). A combined analysis of the GWAS and the replication study showed a strong association at the CYP2A6 locus (), suggesting that this locus is the only major quantitative trait locus associated with CPD in the Japanese population.
