Shared genetic architecture underlying sleep and weight in children

Area of Science:

• Pediatrics
• Genetics
• Sleep Science

Background:

• Shorter sleep duration is a suspected risk factor for childhood obesity, potentially affecting homeostatic processes.
• Both sleep duration and adiposity are heritable, suggesting a possible shared genetic basis for their association.
• Existing research often relies on self-reported sleep, lacking objective measures.

Purpose of the Study:

• To investigate the association between genetic predisposition to obesity and objectively measured sleep duration in children.
• To explore whether shared genetic factors contribute to both obesity risk and shorter sleep duration.

Main Methods:

• Cross-sectional study of 452 Norwegian children at age six.
• Objective measurement of total sleep time (TST) using actigraphy.
• Calculation of a 32-single nucleotide polymorphism (SNP) weighted body mass index (BMI) genetic risk score (GRS).
• Statistical analyses included Pearson's correlations and linear regressions, adjusting for BMI-Standard deviation scores (SDS).

Main Results:

• No significant correlation was found between BMI and TST (r = -0.003, p = 0.946).
• However, the BMI genetic risk score (GRS) was significantly associated with shorter TST (standardized β = -0.11, 95% CI = -0.22 to -0.01) after adjusting for BMI-SDS.
• This is the first study to link genetic obesity risk with objective sleep duration in children.

Conclusions:

• Findings suggest a shared genetic etiology underlies obesity risk and shorter sleep duration in children.
• The association between shorter sleep and obesity may be partly explained by common genetic factors.
• Further research is needed to identify specific biological pathways and genes involved.