BDNF and obesity due to melanocortin 4 receptor deficiency: The results of our study suggest that although obesity is more frequent in the late-onset group of psoriatic patients, for an obese patient belonging to the early-onset group, there is a higher chance to have risk alterations in the LEPR rs1137101 and in the BDNF rs925946 polymorphisms compared to an obese patient from the late-onset or from the general Hungarian population.