GJB2 and deafness: Seven loci in our GWAS where the lead SNP was just below our threshold for significance (P < 5e−7), also overlapped with additional non-syndromal deafness-associated loci: DNFB36, which contains ESPN (espin), DFNB42, which contains ILDR1 (immunoglobulin-like domain-containing receptor 1), DFNB12, which contains CDH23 (cadherin 23), DFNA3A, which contains GJB2 (connexin26), DFNA9, which contains COCH (cochlin), DFNA4B, which contains CEACAM16 (carcinoembryonic antigen-related cell adhesion molecule 16), and DFNB8/10, which contains TMPRSS3 (Transmembrane protease serine 3, Additional file 2).