COL4A1 and obesity due to melanocortin 4 receptor deficiency: We then selected 431 genes that are associated with obesity and identified 5 PAS-SNPs (rs32753534, rs32689441, rs47853609, rs48552886, rs587469149) in 4 obesity-related genes in the Fat line (Abcc6, Col4a1, Lhfpl3, Npc1) and 2 PAS-SNPs (rs243180722, rs38383450) in 2 obesity-related genes in the Lean line (Lsamp, Ppargc1a).