Background/Aims: Picky eating is prevalent among preschoolers and is associated with risk of both underweight and overweight. Although differences in taste perception may be due to genetic variation, it is unclear whether these variations are related to picky eating behavior. The aim of this study was to investigate the association of 6 single nucleotide polymorphisms (SNPs) in 5 candidate genes related to chemosensory perception with picky eating behavior and adiposity in a cohort of preschool-aged children. Methods: Parents of 2- to 5-year-old non-Hispanic white preschoolers (n = 153) responded to survey questions on demographics, and information regarding their child's breastfeeding history and picky eating behavior. Height and weight were measured to calculate body mass index (BMI) z-scores using standard growth charts, and saliva was collected for genotyping. Generalized linear models were used to examine associations between picky eating behavior and BMI z-scores with genetic variation. Results: When controlling for child age, sex, breastfed status, and parent education level, SNPs in TAS2R38 (rs713598) and CA6 (rs2274327) were associated with picky eating behavior in children. There was no association between SNPs and BMI z-scores. Conclusion: Genes related to chemosensory perception may play a role in children's picky eating behavior.

Background: Childhood obesity is a nutrition-related disease with multiple underlying aetiologies. While genetic factors contribute to obesity, the gut microbiome is also implicated through fermentation of nondigestible polysaccharides to short-chain fatty acids (SCFA), which provide some energy to the host and are postulated to act as signalling molecules to affect expression of gut hormones.Objective: To study the cumulative association of causal, regulatory, and tagged single nucleotide polymorphisms (SNPs) within genes involved in SCFA recognition and metabolism with obesity. Design: Study participants were non-Hispanic White (NHW, n = 270) and non-Hispanic Black (NHB, n = 113) children (2-5 years) from the Synergistic Theory and Research on Obesity and Nutrition Group (STRONG) Kids 1 Study. SNP variables were assigned values according to the additive, dominant, or recessive inheritance models. Weighted genetic risk scores (GRS) were constructed by multiplying the reassigned values by independently generated β-coefficients or by summing the β-coefficients. Ethnicity-specific SNPs were selected for inclusion in GRS by cohort. Results: GRS were directly associated with body mass index (BMI) z-score. The models explained 3.75%, 12.9%, and 26.7% of the variance for NHW/NHB, NHW, and NHB (β = 0.89 [CI: 0.43-1.35], P = 0.0002; β = 0.78 [CI: 0.54-1.03], P < 0.0001; β = 0.74 [CI: 0.51-0.97], P < 0.0001).Conclusion: This analysis supports the cumulative association of several candidate genetic variants selected for their role in SCFA signalling, transport, and metabolism with early-onset obesity. These data strengthen the concept that microbiome influences obesity development through host genes interacting with SCFA.

Breath sampling and analysis provide healthcare professionals with a practical, noninvasive diagnostic measurement for children with a variety of gastrointestinal (GI) disorders. New biomarkers found in human breath have been investigated and provide the opportunity to diagnose bacterial overgrowth and other underlying causes of GI dysfunction. Although several protocols have been described previously regarding breath sampling, few have demonstrated the feasibility of collection in young children. This communication introduces a simple game that allows for 3- to 7-year-old children to practice breath exhalation to give a proper breath sample in a relaxed and comfortable environment. The technique described offers clinicians a creative approach for obtaining breath samples from a child by reducing the apprehension and anxiety associated with the research and clinical environment.