FSTL1 and obesity due to melanocortin 4 receptor deficiency: Furthermore, 8 of the 17 CpG loci located in the follistatin like 1 (FSTL1), sortilin related VPS10 domain containing receptor 2 (SORCS2), nuclear respiratory factor 1 (NRF1), DLC1 Rho GTPase activating protein (DLC1), PPARG coactivator 1 beta (PPARGC1B), chimerin 2 (CHN2), and neurexophilin 1 (NXPH1) have previously associated with obesity, diabetes, and insulin pathways [70].