Genetics of Childhood Obesity

Chapter

Abstract

Obesity is increasingly becoming a major health issue for both the USA and the rest of the world, and presents health care systems with a huge economic problem. The rate at which children are becoming obese is dramatically increasingly, particularly since the turn of the twenty-first century. Although environmental factors are known to play a key role, childhood obesity is also known to have an underlying genetic component contributing to its complex etiology. Elucidating the genetic architecture of childhood obesity will not only help prevention and treatment of pediatric cases but also will have fundamental implications for diseases that present later on in life. Furthermore, the execution of genome-wide surveys of childhood obesity have uncovered novel loci that turned out not to be within the detection range in an adult setting as a consequence of environmental factor clouding, supporting the notion that the pediatric setting may be optimal for uncovering obesity genes. This new era of genome-wide association studies (GWAS) is delivering compelling signals associated with obesity, particularly with peer research groups sharing a very strong consensus on what the key loci are that contribute to the pathogenesis of this trait. Although we suggest that the pediatric setting can be harnessed for obesity gene discovery, the fact is that most BMI-associated loci identified to date were found in the adult setting, so there is a requirement to elucidate which of these variants contribute early on in life and therefore predisposing an individual to related diseases in later life. In this chapter, we outline what advances have been made in determining which genetic factors are conferring their effects on childhood obesity and which ones go on to have an impact in adulthood.

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© Springer Science+Business Media New York 2014

Authors and Affiliations

  1. 1.Division of Human GeneticsThe Children’s Hospital of PhiladelphiaPhiladelphiaUSA
  2. 2.Department of Pediatrics, School of MedicineUniversity of PennsylvaniaPhiladelphiaUSA
  3. 3.Children’s Hospital of Philadelphia Research InstitutePhiladelphiaUSA

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