Gene-based genome-wide association study identified 19p13.3 for lean body mass

Lean body mass (LBM) is a complex trait for human health. To identify genomic loci underlying LBM, we performed a gene-based genome-wide association study of lean mass index (LMI) in 1000 unrelated Caucasian subjects, and replicated in 2283 unrelated Caucasians subjects. Gene-based association analyses highlighted the significant associations of three genes UQCR, TCF3 and MBD3 in one single locus 19p13.3 (discovery p = 6.10 × 10−5, 1.65 × 10−4 and 1.10 × 10−4; replication p = 2.21 × 10−3, 1.84 × 10−3 and 6.95 × 10−3; combined p = 2.26 × 10−6, 4.86 × 10−6 and 1.15 × 10−5, respectively). These results, together with the known functional relevance of the three genes to LMI, suggested that the 19p13.3 region containing UQCR, TCF3 and MBD3 genes was a novel locus underlying lean mass variation.