TNNI3K and obesity due to melanocortin 4 receptor deficiency: In this nationally representative study of adolescents, we identify two nominally significant obesity susceptibility variants in EA, rs2112347 (POC5) and rs571312 (MC4R), and one Bonferroni corrected significant variant in HA, rs1514175 (TNNI3K), which showed a comparatively stronger association in smokers vs. nonsmokers.