A recent study identified a biomarker in saliva to identify childhood obesity risk.
Globally, the prevalence of childhood obesity is growing at an alarming rate. According to the Center for Disease Control and Prevention (CDC), in the United States, obesity in children has risen from 13.9 percent in 2000 to 18.5 percent in 2016. Childhood obesity is associated with an increased risk of diabetes, high blood pressure, cardiovascular diseases, and cancer in adulthood. Currently, crude markers such as BMI are used to predict obesity. In several cases, intervention in a child’s obesity occurs after the BMI reaches a certain number.
A recent study, published in BMC Medical Genetics, investigated biomarkers that could identify childhood obesity risk earlier than the BMI designating the individual as obese. In the study, saliva samples were collected from children, aged between three and five years old, and enrolled in the Growing Right Onto Wellness (GROW) trial. At the time of enrollment, the children were not obese. The researchers used saliva because it was non-invasive and easily accessible.
The participants were assigned randomly to two groups. Children with obese mothers were placed in the intervention group and the rest were assigned to the control group. The study followed over 600 parent-child pairs over three years, during which time the participants received behavioural intervention.
The study reports that the majority of the children in the intervention group improved their nutrition, maintained their physical activity, and had sufficient sleep in comparison to the control group. However, around 30 percent of the participants in the intervention group became obese following the three-year study period, suggesting an association between the interaction of genetics and behaviour and health disparities.
A previous study identified methylation, associated with the mother’s BMI and waist circumference at seventeen DNA sites, in the saliva samples of the trial participants, suggesting that the risk of obesity may be passed down from mother to child. In this study, researchers examined the associations between salivary methylation and changes in the child’s BMI after three years. The findings suggest that the methylation differences based on the mother’s BMI as well as other behavioural factors may help predict childhood obesity risk.
The study found that the methylation of NRF1, a gene involved in adipose inflammation, is linked to childhood obesity. Children with NRF1 methylation are at a threefold increased risk of obesity, suggesting this biomarker may need to be further studied for its role in obesity.
The findings support evidence of an epigenetic biomarker in saliva that may predict childhood obesity before it emerges. According to the researchers, the findings are important to better understand the risk factors for childhood obesity and help pave the way for early intervention and prevention.
Written by Ranjani Sabarinathan, MSc
Rushing A., Sommer EC, Zhao S et al. (2020). Salivary epigenetic biomarkers as predictors of emerging childhood obesity. BMC Medical Genetics. doi: 10.1186/s12881-020-0968-7
Biomarker in saliva predicts childhood obesity risk. (2020, March 6). Retrieved from https://www.eurekalert.org/pub_releases/2020-03/vumc-bis030620.php
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