Comparison of the Gut Microbiota Composition in Caucasian Hispanic and Caucasian Non-Hispanic Children With and Without Obesity

I. SPECIFIC AIMS There are a vast number of microbes in the human gastrointestinal tract (GI) including bacterial, fungal and protozoal microorganisms which all together make our microbiome. Over the last years evidence has shown that the GI microbiome is linked with our overall health including obesity risk. The GI microbiota can influence both sides of the energy balance that includes factors influencing energy utilization from the diet and factors that play a role in the regulation of energy expenditure and storage by influencing host genes (1, 2). Studies of demonstrated that overweight and obesity rates are among the highest for Hispanic children in the United States. It is estimated that in the US 47% of Hispanic children are overweight and 31% have obesity, compared to 35% and 21% respectively for Caucasian non-Hispanic children. Literature has shown environment factors are associated with childhood obesity in Hispanic children including: parental influences, screen time, physical activity behavior, socioeconomic status/food security, and sleep duration (3,4). Thus far there have been no studies having investigated if there are significant differences in the gut microbiome of Hispanic children; moreover, whether these differences (taxonomy or gene expression) puts them at higher risk to develop obesity compared other ethnic groups.

The investigators predict there are significant GI microbiome differences between Caucasian non-Hispanic children and Hispanic Children.

Aim: Confirm differences in microbiome between Caucasian non-Hispanic children (with and without obesity) and Hispanic children (with and without obesity) in this pilot study.

Hypothesis: Hispanic children will have a lower fecal bacterial diversity compared to Caucasian non-Hispanic children that is associated with more overall adiposity and impaired glucose homeostasis determined by:

A) Next generation metagenomic "whole genome/shotgun" sequencing of DNA from fecal samples of cohorts which includes Hispanic children with obesity, Hispanic children without obesity, Caucasian non-Hispanic children with obesity and Caucasian non-Hispanic children without obesity.