Isolation of a cyp2b10-like cDNA and of a clone derived from a cyp2b10-like pseudogene

By screening Balb/c male mouse liver cDNA library with a rat CYP2B1 cDNA probe, we have isolated a 1795 bp cyp2b10-like clone, referred to as P16. Its sequence exhibited 34 base differences (98% similarity) with the cyp2b10 published sequence, together with a 97% identity at the amino acid sequence level. By RT-PCR and PCR analyses with Balb/c female and male liver RNA and genomic DNA, using a region showing 8 base differences between the P16 and the cyp2b10 sequences, we have confirmed the identity of our cloned cDNA, and failed in finding a PCR product exhibiting a sequence 100% identical with that of cyp2b10. Our results therefore suggest that the P16 sequence is the authentic cyp2b10 sequence. We have also isolated a partial clone, P21, which 1609 bp sequence overlapped with that of P16, except for a T-->G transversion, giving rise to a premature TGA stop codon, indicating that it was derived from a pseudogene.