Moreover, Wu et al. observed that the methylation levels of 100 CpG sites corresponding to 66 genes were different between the GDM group (n = 11) and the control group (n = 11), in the peripheral blood of pregnant women in their first trimester, further suggesting that the DNA methylation status of 5 CpG sites, in the COPS8, PIK3R5, HAAO, CCDC124, and C5orf34 genes could be used as clinical biomarkers of GDM17. The gene discussed is C5orf34; the disease is gestational diabetes.