FTO and obesity due to melanocortin 4 receptor deficiency: Additionally it hasbeen suggested that the polymorphisms located in noncoding sequences (intron 1 and2) within FTO interact with the promotor region of another gene inthe neighborhood, called IRX3. Consistent with this,FTO polymorphisms associated with obesity alter the expressionof IRX3 in human brains, which is related with regulation of body mass andcomposition (Smemo et al.,2014).