FNDC5 and gestational diabetes: At the same time, Yuksel and coworkers [131] investigated the relationship between maternal and cord blood irisin in relation to maternal glycemic status and found that the irisin level in the serum of GDM mothers was significantly lower than in the control cohort (258.3 ± 127.9 vs. 393 ± 178.9 ng/mL, respectively).