- 2015 research suggests rs1421085 may be the causal variant blog summary
- Within the FTO gene, rs9930506 showed the strongest association with BMI (p = 8.6 *10-7), hip circumference (p = 3.4 * 10-8) and weight (p = 9.1 * 10-7). homozygotes for the rare "G" allele were 1.3 BMI units heavier than homozygotes for the common "A" allele. More than 30 additional SNPs in or near the FTO gene were also studied, but they are co-inherited most of the time with the rs9930506 SNP and therefore are unlikely to represent independent risk factors. These co-inherited SNPs include rs1421085, rs9937053, rs8043757, rs3751812, rs9923233, rs9932754, and rs9922619. [PMID 17658951]
- Note: The three FTO SNPs, rs1421085, rs17817449, and rs9939609, are in strong linkage disequilibrium (pairwise r2>0.97), and there are two primary haplotypes, C-G-A (42.0%; this is the haplotype representing obesity risk) and T-T-T (55.5%).
- Another report fingers rs1121980 within the FTO gene as having the strongest association to early onset obesity compared to several other SNPs all in the same linkage block. [PMID 18159244]
The earlier study also had conclusions with regard to another gene:
- Within the PFKP gene, rs6602024 showed very strong association with BMI (p = 4.9 * 10-6). Homozygotes for the rare "A" allele of this SNP (minor allele frequency = 0.12) were 1.8 BMI units heavier than homozygotes for the common "G" allele. They did not replicate association between rs6602024 and obesity-related traits in the GenNet sample, although they found that in European Americans, Hispanic Americans and African Americans, homozygotes for the rare "A" allele where, on average, 1.0 - 3.0 BMI units heavier than homozygotes for the more common "G" allele. [PMID 17658951]
“Genetic associations with traits in 23andMe customers.” 23andMe White Paper.