MTHFR Polymorphisms in Girls with Anorexia Nervosa: Implications on Body Weight

The development of atypical vs typical anorexia nervosa (AN) might be explained by the genetic background. We assessed the link between the subtypes of AN and the genetic polymorphisms of the thrombotic panel and the methyltetrahydrofolate reductase (MTHFR) gene. This cross-sectional pilot study recruited 48 girls with AN and 10 age-matched control girls with normal menstruation. We recorded anthropometric parameters and obtained blood samples for genotyping and hormonal assessment. Classification of AN was performed according to the DSM-V criteria. Girls with AN had 2.66 times higher odds of carrying at least one genetic polymorphism from the MTHFR panel (C677T and A1298C) compared with girls without AN (OR = 2.660, p-value = 0.041; CI 95% 1.057-6.720). The presence of atypical vs typical AN was associated independently with the presence of any of the assessed MTHFR polymorphisms (C677T, OR = 4.929, 95% CI 1.076-22.579, p-value = 0.040; A1298C, OR = 0.097, 95% CI 0.011-0.866, p-value = 0.037) in age and estrogen adjusted models. The atypical presentation of AN is mainly linked with higher prevalence of the MTHFR C677T and lower prevalence of the A1298C polymorphism.