Expression of the DNA repair gene XRCC1 in baboon tissues.

XRCC1 is a DNA repair gene involved in rejoining DNA strand-breaks. We used baboon as an animal model to determine the levels of XRCC1 gene expression in different tissues. Baboons were selected because they are evolutionarily closely related to humans. A single 2.2 kb transcript was detected in all tissues tested by northern blot analysis, with variations in levels of expression among tissues. The expression levels of XRCC1 were measured by quantitative RNase protection assays. XRCC1 mRNA levels were significantly higher in testis than those in other tissues. A mean value of 24.6 x 10(5) XRCC1 transcripts per micrograms DNA was found in testis, while 10.5 x 10(5) in ovary, 9.8 x 10(5) in brain, 8.5 x 10(5) in liver, 6.8 x 10(5) in kidney, 6.5 x 10(5) in heart, 6.4 x 10(5) in lymph nodes, 6.0 x 10(5) in lung and 4.9 x 10(5) in spleen were found.