Ince-Askan H, Mandaviya PR, Felix JF, et al. - In 80 blood samples from children born to mothers with rheumatoid arthritis (RA), genome-wide DNA methylation was calculated at cytosine-phosphate-guanine (CpG) sites, using the Infinium Illumina HumanMethylation 450K BeadChip by the researchers in order to ascertain whether the DNA methylation profile of children born to mothers with RA varied from that of children born to mothers from the general population and to discover whether any variations in methylation were correlated with maternal RA disease activity or medication use during pregnancy. Among blood samples of children born to mothers with RA and the control blood samples, a total of 147 CpGs were differentially methylated. The cg06642177, cg08867893, cg06778273, cg07786668, and cg20116574 were the five most significantly correlated CpGs. The variations in methylation were not related to maternal RA disease activity or medication use during pregnancy. Hence, DNA methylation at 147 CpGs varied between children born to mothers with RA and children born to mothers from the general population. However, whether the recognized relationships were causal remained unknown, and if so whether they were caused by the disease or treatment.