ANALYSIS OF THE PAX-3 GENE IN THE MOUSE MUTANT SPLOTCH

In a linkage analysis of Pax-3 and splotch no recombinations were found in 117 backcross mice. Molecular analysis of Pax-3 in three alleles of splotch shows a number of significant alterations to the Pax-3 gene. In Sp/Sp embryos, cDNA PCR analysis reveals a shortened transcript in which exon 4 of Pax-3 is deleted due to mutation of the splice acceptor site of intron 3. In the Sp(4H) allele, the Pax-3 gene is deleted and in Sp(d) embryos, Pax-3 expression is significantly lower than that in normal littermate embryos. The linkage analysis, shortened Pax-3 transcript in Sp, and deletion of Pax-3 in Sp(4H) described here, together with the previous report of an intragenic deletion in Pax-3 in Sp(2H) mice and the deletion of Pax-3 in Sp(r) mice, provide strong evidence for the allelic identity of Pax-3 and Sp. © 1993 Academic Press. All rights reserved.