Krótka charakterystyka genetycznych uwarunkowań otyłości - jak wpaść na trop właściwego rozpoznania

Obesity is a serious health problem in the modern society. Nevertheless, in spite of the intensive research efforts, only few genes that affect adipose tissue have been characterised. The most common form of obesity is determined by an interaction between the permissive environment and the host of polymorphisms located in genes throughout the genome that influence the individual susceptibility to gain weight. There exist also the rare cases of obesity caused by mutations in the genes of the leptin-melanocortin pathway e.g. congenital leptin or proopiomelanocortin deficiency. The most frequent cause of monogenic obesity is the mutation of the melanocortin-4 receptor that seems to follow an autosomal dominant mode of inheritance. Furthermore, the literature gives a description of at least 30 genetic syndroms with obesity as a major trait. However, in each case of the syndromic obesity the excess of the fat mass is accompanied by the specific pattern of dysmorphic traits, different congenital malformations and/or mental retardation. The focus of this review is to distinguish clinical features that can aid to establish the right clinical diagnosis in the individual suspected of the syndromic or non-syndromic monogenic form of obesity. Moreover, we present the current knowledge about the genetic background, underlying pathogenic mechanisms and detailed characteristics of such diseases.