MAPPING OF 22 EXPRESSED SEQUENCE TAGS ISOLATED FROM A PORCINE SMALL-INTESTINE CDNA LIBRARY

Complementary DNA sequences were selected from a resource of tentative ly identified clones from a porcine small intestine cDNA library. Fort y PCR primer pairs were designed to amplify 101-309 base pairs of the 3' untranslated region of the genes. The PCR conditions were optimized by altering both formamide and magnesium concentrations on samples of pig, mouse, and hamster DNA. Twenty primer pairs that, under stringen t conditions, were pig-specific and amplified the expected fragments w ere chosen for regional assignment in a pig/rodent hybrid cell panel. Furthermore, 22 primer pairs were chosen to amplify DNA from the paren tal animals of the PiGMaP shared reference families in order to detect possible polymorphisms. Primer pairs that generated polymorphisms wer e used for genetic mapping. A total of 22 porcine expressed sequence t ags (ESTs) were cytogenetically or genetically mapped by this approach . Twelve of the mapped ESTs could be added to the human-porcine compar ative map.