MC4R and obesity due to melanocortin 4 receptor deficiency: In addition, spontaneous mutations in the Alstrom syndrome 1 gene encoding for a protein localized to centrosomes and appetite-sensing neuronal cilia (foz/foz mice), Pparα-/- knockout mice, and melanocortin receptor 4 knockout (Mc4r-/- mice) lead to overeating, obesity and IR, but do not progress NASH or HCC.