Genetic epidemiology and molecular genetics of obesity: results from the Quebec Family Study

Obesity is a complex disease affecting about one third of the adult population in industrialized countries. Research conducted over the past 10 years in the fields of genetic epidemiology and molecular genetics has clearly established that obesity and the susceptibility to gain or lose weight are partly determined by our genes. Based on results from the Quebec Family Study, the heritability of the various obesity phenotypes ranges from about 10 % to 50 % and segregation analyses suggest that one or a few genes, with an autosomal recessive mode of inheritance, have a major effect on these phenotypes. The current human obesity gene map based on results from animal and human studies indicates that all chromosomes, with the exception of the Y chromosome, include genes or loci potentially involved in the etiology of obesity.