I disturbi del comportamento alimentare nell'era delle neuroscienze: Ruolo della vulnerabilità genetica

Anorexia nervosa, bulimia nervosa, binge eating disorder and the several subthreshold eating disorders (EDs) are psychiatric disorders which often lead to chronicization and to the alteration of social functioning. The development of neurosciences in the last years has allowed progress in the study of the genetic vulnerability in EDs. Studies performed on families, twins and molecular genetic studies showed the fundamental role of biologic factors in the development and maintenance of EDs. The candidate genes examined are those coding for neurotransmitters, neurohormones and growth factors. With more detail, though there is a wide heterogeneity, the 5HT2A gene and the role of the brain derived nerve factor (BDNF) have received the major interest. Another field of research is that of endophenotypes. From this point of view, the risk factors with a greater heritability may be some stable traits as impulsiveness, obsessiveness, perfectionism, body image disorders, temperamental traits, sensitivity to dieting and to the related societal messages. The endophenotypes have the advantage of making the concept of vulnerability more usable for the clinician. The identification of the genetic elements gives a new explanation and enriches the previous psychological and family theories and the study of the impact of environment on genetic vulnerability. In the next future the research will focus on the gene-environment relation and on the reciprocal enhancement of risk factors. The role of family and familiarity is discussed.