BDNF Val66Met polymorphism and brain volumes in multiple sclerosis

Brain derived neurotrophic factor (BDNF) regulates several CNS physiological and pathological processes. To investigate in multiple sclerosis (MS) patients, the relationship between the Val66Met polymorphism of BDNF and clinical markers of disease activity and MRI markers of focal and diffuse brain pathologies. 45 MS patients and 34 healthy controls (HCs) were genotyped and subjected to clinical-MRI examination. Global white matter fraction (gWM-f), gray matter-f (GM-f), cerebrospinal fluid-f (CSF-f), and abnormal WM-f were measured. We studied 26 Val/Val and 19 Val/Met patients and 23 Val/Val and 11 Val/Met HCs. We found that Val/Val patients had lower GM-f and higher CSF-f than Val/Val HCs; such differences were not statistically significant comparing Val/Met patients to HCs. The regression analysis showed that both Val/Met genotype and relapse number were associated with lower CSF-f. Our data suggest that Met allele might be a protective factor against MS as it is associated to a lower brain atrophy.