Multi-Ancestry Study Leads to BMI-Associated Methylation Marks

In the American Journal of Human Genetics, a team from Emory University, Peking University, and elsewhere presents findings from an epigenome-wide association study meta-analysis focused on body mass index (BMI)-related DNA methylation marks. Using summary statistic data from half a dozen multi-ethnic epigenome-wide association studies encompassing more than 17,000 participants, the researchers initially found almost 1,300 cytosine-guanine nucleotide pair (CpG) methylation marks linked to BMI. After validating 1,238 of the BMI-related CpG methylation sites using data from another 4,822 individuals, they explored cross-ancestry and ancestry-specific associations, ultimately developing an epigenetics-based approach for predicting BMI based on data at almost 400 DNA methylation sites that were trained in nearly 3,900 individuals and tested in 1,297 participants in relation to other cardiovascular and metabolic markers. "Individuals whose methylome-predicted BMI overestimated their BMI (high epigenetic BMI) had significantly higher glucose and triglycerides and lower [high-density lipoprotein (HDL)] cholesterol and [low-density lipoprotein (LDL)] cholesterol compared to accurately predicted BMI," the authors note, while those with BMI underestimates with the methylation-based predictor "had significantly higher HDL cholesterol and lower glucose and triglycerides."