Figure 1.

Circulating unmethylated and methylated INS DNA in lean and obese adults. DNA was isolated from serum of subjects and bisulfite converted as described previously [38]. Primers and dual-fluorescent probes for interrogating methylation at CpG position −69 at the human INS gene using droplet digital PCR were described previously [26,34]. Values were normalized for DNA recovery, and back-calculated to the volute of serum used in the DNA isolation (A) Circulating unmethylated INS DNA; (B) circulated methylated INS DNA. A Kruskal–Wallis (non-parametric) test was employed followed by a Dunnett’s post-test (to compare values to Lean controls). Statistical significance was assumed at p < 0.05. Data are presented as mean ± SEM.