Expression stability of ACTB, 18S, and GAPDH in human placental tissues from subjects with PCOS and controls: GAPDH expression is increased in PCOS

Purpose The aim was to assess the expression stability of three commonly used reference genes, namely, beta-actin (ACTB), 18S ribosomal RNA (18S), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), in placental tissue obtained from pregnant women with polycystic ovary syndrome (PCOS) and healthy controls. Methods mRNA was isolated after delivery from the placentae of 10 PCOS and 10 control women with term, uncomplicated, singleton pregnancies. The expression of ACTB, 18S, and GAPDH was analyzed using real-time polymerase chain reaction (RT-PCR). Gene expression stability was evaluated with the RefFinder, GeNorm, Normfinder, BestKeeper, and Delta-Ct tools. Results ACTB was ranked as the most stably expressed gene, followed by 18S. The expression of GAPDH varied considerably in both studied groups, while it was increased in PCOS versus controls (5.3-fold, p < 0.05). Conclusions ACTB is an appropriate reference gene for placental gene expression studies in women with PCOS, whereas GAPDH is unfit for such a role, as its placental expression is increased in PCOS.

Automated summary

This study assessed the expression stability of three commonly used reference genes (ACTB, 18S, and GAPDH) in placental tissue obtained from pregnant women with PCOS and healthy controls. The results showed that ACTB was the most stable gene, followed by 18S, while the expression of GAPDH varied considerably and was increased in PCOS.