β-Glucuronidase is a suitable internal control gene for mRNA quantitation in pathophysiological and non-pathological livers

• GUSB is the most suitable control gene for quantitative mRNA studies on liver.
• GUSB showed stable expression in pathophysiological and non-pathological livers.
• Expression of housekeeping genes was not always stable in diseased liver.
• It is necessary to statistically determine the best control gene for each exam.

The level of expression of housekeeping genes is in general considered stable, and a representative gene such as glyceraldehyde-3-phosphate dehydrogenase is commonly used as an internal control for quantitating mRNA. However, expression of housekeeping genes is not always constant under pathological conditions. To determine which genes would be most suitable as internal controls for quantitative gene expression studies in human liver diseases, we quantified 12 representative housekeeping genes in 27 non-cancerous liver tissues (normal, chronic hepatitis C with and without liver cirrhosis). We identified β-glucuronidase as the most suitable gene for studies on liver by rigorous statistical analysis of inter- and intra-group comparisons. We conclude that it is important to determine the most appropriate control gene for the particular condition to be analyzed.