Genomic structure and refined chromosomal localization of the mouse Ptch2 gene

The vertebrate Patched 2 (Ptch2) gene encodes a putative membrane-embedded protein which may have roles in Hedgehog signaling during development and in tumorigenesis. We determined the genomic structure of the mouse Ptch2 gene and show that Ptch2 is composed of 22 exons spanning approximately 18 kb of genomic DNA. The exon-intron boundaries were found to be conserved within the human and mouse Ptch2 genes. Analysis of the 5' flanking region revealed a CpG island, the putative promoter region and the transcriptional start site while a polyadenylation signal as well as a mRNA destabilizing motif were identified in the 3' flanking region. Single-strand conformation polymorphism analysis was used to map mouse Ptch2 to chromosome 4 between the microsatellite markers D4Mit20 and D4Mit334.