RP1L1 and obesity due to melanocortin 4 receptor deficiency: It may be useful, as a first strategy, to concentrate efforts on studying effects of non-synonymous variants identified within the 13 candidate genes of the region, PRAG1, MFHAS1, PPP1R3B, TNKS, MSRA, PRSS55, RP1L1, PINX1, MTMR9, FAM167A, BLK, GATA4, and CTSB. It may also be useful to expand genetic studies to include patients with obesity-related phenotypes and studying the expression levels of candidate genes in relevant tissue may also give additional clues regarding their roles in disease-related phenotypes.