The rat adenine phosphoribosyltransferase sequence shows evolutionary rate variation among exons in rodents

The complete genomic sequence of the rat APRT gene is described and compared with published mammalian sequences. The rat APRT gene organization is typical of other rodent APRTs with five exons, one large intron of 993 bp, and three smaller introns averaging 145 bp. Because complete sequences for mouse and Chinese hamster APRT are also known, it is possible to compare the evolutionary rates of change in the exons with those of the introns. The …