Molecular evolution of Aldolase A pseudogenes in mice: Multiple origins, subsequent duplications, and heterogeneity of evolutionary rates

The Aldolase multigene family comprises three functional genes (A, B, and C ) with tissue-specific expression regulated during ontogeny. DGGE analysis and nucleotide sequencing reveal a family of retropseudogenes of type A in species of Mus. Significant variation in rates of evolution of Aldolase A r etropseudogenes is apparent. Our analyses demonstrate that (1) multiple eve nts of retrotransposition are needed to account for the diversity of Aldola se A processed pseudogenes found in mice; (2) some of these sequences have undergone further duplication subsequent to the original retrotransposition event; (3) the patterns of nucleotide substitution are broadly comparable with previous estimates; and (4) estimates of rates of divergence for this array of sequences are up to four times higher than those reported in the l iterature.