Nucleotide Substitution Pattern in Mitochondrial Cytochrome b Pseudogenes of Ten Species in Galliformes

摘要

Mitochondrial cytochrome b pseudogene sequences (numts) in ten birds of the order Galliformes were studied for the pattern of nucleotide substitutions. Our results showed that nucleotide transitions were much more common than transversion in the numts. No transversions were detected in the numts of Chrysolophus pictus and Chrysolophus amherstiae. Moreover, there was no evidence that the nucleotide substitutions could have significant neighboring biases (P > 0.05) in the Cyt b gene numts. The identified nucleotide deletions ranged from 0 base pair (bp) to 12 bp, while only a thymidine was inserted at the 323th site of the numt sequence of Numida meleagris. Unexpectedly, 2 bp deletions was more frequent than 3 bp deletions and 5 bp deletions, which indicated the changes of encoding amino acids. Both mitochondrial Cyt b gene and the corresponding numt were abundant in the base contents of adenine (A) and thymidine (T).