The FTO gene polymorphism rs9939609 is associated with obesity and disability in multiple sclerosis patients

Obesity is a well-known risk factor for multiple diseases including multiple sclerosis (MS). Polymorphisms in the fat-mass obesity (FTO) gene have been consistently found to be associated with obesity, and recently found to increase the risk of developing MS. We therefore assessed the common FTO gene polymorphism (rs9939609) in relation to obesity, risk of developing MS and its disability in a cohort of MS patients. A cohort of 200 MS patients (135 females and 65 males) were genotyped for the FTO rs9939609 polymorphism. Using both logistic and linear regression we assessed the relationship between the variant and the selected phenotypes under both an additive and recessive genetic models. The A-allele was found to be associated with being overweight/obese in MS patients (OR = 2.48 (95% CI 1.17–5.29); p = 0.01). In addition, The A-allele was also found to be associated with increased MS disability (β = 0.48 (95% CI 0.03–0.92); p = 0.03). However, no association was found with risk of developing MS (p > 0.05). Moreover, our association with obesity is consistent with previous reports, whereas the association with disability is novel and warrants further investigation on the role of FTO in disease progression.