Download Aslibekyan and team identify novel loci associated with BMI and

Aslibekyan and team identify novel loci associated with BMI and waist circumference
Published on UAB School of Public Health (http://www.soph.uab.edu)
Aslibekyan and team identify novel loci associated with BMI
and waist circumference
Stella Aslibekyan, PhD, assistant professor in the Department of Epidemiology, recently conducted
an epigenome-wide analysis of DNA methylation and obesity traits. UAB co-investigators are
department colleagues statistician Jin Sha; assistant professor Ryan Irvin, PhD, MS; assistant
professor Bertha Hidalgo, PhD, MPH; and professor and chair Donna K. Arnett, PhD, MSPH; as well as
assistant professor Degui Zhi, PhD, and professor Hemant K. Tiwari, PhD, in the Department of
Biostatistics, Section on Statistical Genetics.
The study measured DNA methylation patterns in CD4+ T-cells using the Illumina Infinium
HumanMethylation450 array in a total of 991 participants of the Genetics of Lipid Lowering Drugs
and Diet Network (GOLDN). Methylation is believed to be linked to gene expression, turning genes
“up” or “down” in response to environmental stimuli. The GOLDN study modeled methylation at
individual cytosine-phosphate-guanine (CpG) sites across the entire genome as a function of body
mass index (BMI), while adjusting for age, gender, study site, T-cell purity, smoking, and family
relationships. Similar models were fit for waist circumference (WC).
According to the study, epigenome-wide significant associations between eight CpG sites and BMI
and five CpG sites and WC were found, replicating the highest hits in whole blood samples from the
Framingham Heart Study (n = 2,377) and the Atherosclerosis Risk in Communities Study (n = 2,097);
top findings were in “CPT1A (meta-analysis P = 2.7 × 10(-43) for BMI and 9.9 × 10(-23) for WC),
PHGDH (meta-analysis P = 2.0 × 10(-15) for BMI and 4.0 × 10(-9) for WC), CD38 (meta-analysis P =
6.3 × 10(-11) for BMI and 1.6 × 10(-12) for WC), and long intergenic non-coding RNA 00263 (metaPage 1 of 2
Aslibekyan and team identify novel loci associated with BMI and waist circumference
Published on UAB School of Public Health (http://www.soph.uab.edu)
analysis P = 2.2 × 10(-16) for BMI and 8.9 × 10(-14) for WC), regions with biologically plausible
relationships to adiposity.” For the finding in CPT1A, the methylation status of the region has
previously been linked to gene expression and other disease phenotypes such as triglycerides and
very low density lipoprotein cholesterol.
“This large-scale epigenome-wide study discovered and replicated robust associations between DNA
methylation at CpG loci and obesity indices, laying the groundwork for future diagnostic and/or
therapeutic applications,” notes Dr. Aslibekyan.
To read “Epigenome-wide Study Identifies Novel Methylation Loci Associated with Body Mass Index
and Waist Circumference,” published online in July 2015 in the journal Obesity, click here.
Page 2 of 2