NPC1 and obesity due to melanocortin 4 receptor deficiency: In addition, PAS-SNPs have also been identified in other obesity-related genes: Abcc6 and Npc1 in the Fat line and Lsamp (limbic system-associated membrane protein) in the Lean line, as well as in Arhgap8 (Rho GTPase activating protein 8) in the Fat line, which is localised in the dominant Fob2 (Horvat et al. 2000).