So far, three studies have examined whether rare variants in FTO are disproportionally represented in obese or lean individuals through sequencing of the exons.137-139 Together, they identified at least 45 low-frequency coding variants, but none of the studies found evidence of an enrichment of any of these variants, individually or combined, in either obese or lean indiviudals, even though some of the variants are predicted to have deleterious effects of FTO’s function.137-139
