Genetics of Common Obesity in Children and Adolescents

Childhood obesity is a multifactorial public health problem worldwide. Genetic variation influences the predisposition to develop obesity at early stages of life. Childhood obesity may be classified as syndromic, monogenic, or polygenic depending on the genetic component. Polygenic obesity is the most frequent, having an important interaction with environmental factors. A scoping review was conducted to identify existing literature on the association between common genetic variation and obesity-related traits in children and adolescents. We retrieved 180 studies that were classified as genome-wide studies, meta-analyses targeting selected variants, and original studies with a targeted genotype approach. Most genome-wide meta-analyses have been conducted in Caucasian populations and have collectively identified over 100 variants in approximately 40 genes associated with obesity-related traits. The identified genes are related to appetite regulation and energy expenditure, although in some cases, their function remains to be elucidated. Studies analyzing targeted variants have replicated some findings across populations. Some genotypes have shown varying associations, probably due to differences in study design, populations, and sample size. The effects of genetic variation on common childhood obesity require further study in diverse populations. In addition, the functional effects and clinical significance of these variants require further research.