MOLECULAR GENETIC-ANALYSIS OF THE TA25H DELETION - EVIDENCE FOR ADDITIONAL DELETED LOCI

Seventeen linking clones sublocalized to the central region of the mouse X Chromosome (Chr) were screened against genomic DNA from male mice carrying the tabby-25H (Ta25H) deletion. Two of these linking clones, lambda-EM131 and lambda-EM169, were found to be deleted in Ta25H/Y animals. Genetic mapping through Mus musculus domesticus/Mus spretus interspecific backcross progeny, segregating for the original tabby (Ta) gene mutation, was utilized to order these markers and to define nearest flanking markers to the Ta25H deletion (lambda-EM140 and lambda-EM171). The size of the Ta25H deletion was thus estimated as up to 4.5 centiMorgans (cM). The order of markers, proximal to distal, was found to be lambda-EM140/lambda-EM131, mouse androgen receptor gene (Ar)/lambda-EM169, Ta/lambda-EM171. A putative CpG-rich island and a highly evolutionarily conserved DNA probe were isolated from the DXCrc169 locus which co-segregates with the Ta locus in this study.