High-throughput genotyping with primer extension fluorescent polarization detection

Overview of Admixture Mapping

Admixture mapping is a powerful method of gene mapping for diseases or traits that show differential risk by ancestry. Admixture mapping has been applied most often to Americans who trace ancestry to various combinations of Native Americans, Europeans, and West Africans. Recent developments in admixture mapping include improvements in the methods and reference data needed to make inferences about ancestry as well as extensions of the mapping approach in the framework of linear mixed models. This overview outlines the key concepts of admixture mapping. It describes approaches for inferring local ancestry and provides strategies for performing admixture mapping depending on the study design. Finally, linkage analysis, association analysis, and admixture mapping are compared, with an emphasis on integrating admixture mapping and association testing. Published 2023. This article is a U.S. Government work and is in the public domain in the USA.

Individual genetic variations related to satiety and appetite control increase risk of obesity in preschool-age children in the STRONG kids program

BACKGROUND/AIMS

The burden of the childhood obesity epidemic is well recognized; nevertheless, the genetic markers and gene-environment interactions associated with the development of common obesity are still unknown. In this study, candidate genes associated to satiety and appetite control pathways with obesity-related traits were tested in Caucasian preschoolers from the STRONG Kids project.

METHODS

Eight genetic variants in genes related to obesity (BDNF, LEPR, FTO, PCSK1, POMC, TUB, LEP, and MC4R) were genotyped in 128 children from the STRONG Kids project (mean age 39.7 months). Data were analyzed for individual associations and to test for genetic predisposition scores (GPSs) with body mass index (BMI) and anthropometric traits (Z-scores, e.g. height-for-age Z-score, HAZ). Covariates included age, sex, and breastfeeding (BF) duration.

RESULTS

Obesity and overweight prevalence was 6.3 and 19.5%, respectively, according to age- and sex-specific BMI percentiles. Individual genetic associations of MC4R and LEPR markers with HAZ were strengthened when BF duration was included as a covariate. Our GPSs show that, as the number of risk alleles increased, the risk of higher BMI and HAZ also increased. Overall, the GPSs assembled were able to explain 2-3% of the variability in BMI and HAZ phenotypes.

CONCLUSION

Genetic associations with common obesity-related phenotypes were found in the STRONG Kids project. GPSs assembled for specific candidate genes were associated with BMI and HAZ phenotypes.