mRNA-expression of often used house-keeping genes and the relation between RNA and DNA are sex steroid-dependent parameters in human myometrium and fibroids.

The content of RNA and DNA in human myometrium and fibroids obtained at different endocrine conditions varied, with the highest RNA/DNA ratio in tissues from pregnant patients, intermediate ratios in women during the menstrual cycle and the lowest in tissues from postmenopausal and GnRHa-treated patients. mRNA expression of two house-keeping genes, gamma-actin and GAPDH, was highest in myometrium from pregnant women, intermediate in untreated women of fertile age and lowest in tissues from GnRHa-treated and postmenopausal women. To control for degradation of nucleic acids when measuring mRNA expression, we suggest additional analysis of gene(s), where the expression pattern is known, and that expression, whenever possible, is related to DNA, which is a more stable parameter than RNA and total nucleic acids, when there are differences in proliferation between tissues and/or groups of patients.