Homologs of genes and anonymous loci on human Chromosome 13 map to mouse Chromosomes 8 and 14

Abstract

To enhance the comparative map for human Chromosome (Chr) 13, we identified clones for human genes and anonymous loci that cross-hybridized with their mouse homologs and then used linkage crosses for mapping. Of the clones for four genes and twelve anonymous loci tested, cross-hybridization was found for six, COL4A1, COL4A2, D13S26, D13S35, F10, and PCCA. Strong evidence for homology was found for COL4A1, COL4A2, D13S26, D13S35, and F10, but only circumstantial homology evidence was obtained for PCCA. To genetically map these mouse homologs (Cf10, Col4a1, Col4a2, D14H13S26, D8H13S35, and Pcca-rs), we used interspecific and intersubspecific mapping panels. D14H13S26 and Pcca-rs were located on the distal portion of mouse Chr 14 extending by approximately 30 cM the conserved linkage between human Chr 13 and mouse Chr 14, assuming that Pcca-rs is the mouse homolog of PCCA. By contrast, Cf10, Col4a1, Col4a2, and D8H13S35 mapped near the centromere of mouse Chr 8, defining a new conserved linkage. Finally, we identified either a closely linked sequence related to Col4a2, or a recombination hot-spot between Col4a1 and Col4a2 that has been conserved in humans and mice.

Zooming in on the Human–Mouse Comparative Map: Genome Conservation Re-examined on a High-Resolution Scale

“…Whereas high resolution IB maps permit gene order and spacing to be established with considerable accuracy, FISH mapping generally permits positions of related human genes to be defined only on the level of chromosome bands or, at best, subbands (e.g., Koizumi et al 1995;Pilz et al 1995;MGD 1997; the bulk of the data summarized in Figs. 1 and 2 are of this type).…”