A family of repeated DNA sequences, one of which resides in the second intervening sequence of the mouse dihydrofolate reductase gene

One member of a repeated sequence family has been found in the second intron of the mouse dihydrofolate reductase gene. The family consists of approximately 20 members/haploid genome, two of which have been sequenced and found to contain a 480-base pair region of homology with a significant amount of sequence divergence. Rat, Chinese hamster, Syrian hamster, and human DNAs contain homologous repetitious elements, and the four rodent species have a member of this family associated with the dihydrofolate reductase gene.