Chromosomal assignments of 19 porcine cDNA sequences by FISH

A major step towards a comparative map of the porcine genome was taken by ZOO-FISH chromosome painting that allowed determination of synteny conservation between human and pig. However, internal rearrangements of gene order within regions of synteny conservation are not uncovered in these experiments. There is, therefore, still a need to increase the resolution of the comparative map consisting of conserved sequences either by linkage mapping or by regional physical mapping. The sequencing of 839 clones from a pig intestinal cDNA library has provided a generous resource of pig Type I markers which so far have been used for mapping of a total of 47 pig genes by linkage or hybrid cell analysis. However, the potential of FISH mapping for improving the comparative map by accurate assignment of a larger set of cDNA clones has not previously been investigated in domestic animals. We therefore selected 48 of the pig cDNA clones from the collection described by Wintero and associates (1996). With a few exceptions, the clones selected were cDNAs where the underlying gene had been tentatively identified by sequence comparison.