There is evidence for co-regulatory mechanisms between FTO and RPGRIP1L, with a possible overlapping regulatory region within intron 1 of FTO that contains at least two putative transcription factor binding sites (CUX1), as mentioned above, one of which overlaps with other obesity associated SNPs.27,28 It remains a possibility that the association between FTO SNPs and body weight regulation is mediated through changing the expression of both FTO and RPGRIP1L.
