ASSIGNMENT OF THE GENE FOR PORCINE INSULIN-LIKE GROWTH-FACTOR-1 (IGF1) TO CHROMOSOME-5 BY LINKAGE MAPPING

Investigation of published sequence data from the porcine insulin-like growth factor 1 (IGF1) gene, resulted in the detection of a microsate llite in the first intron of the gene. Polymerase chain reaction (PCR) primers flanking the (CA)(19) repeat were constructed. Polymorphism a nd Mendelian segregation were documented in a three-generation pedigre e and allele frequencies were determined in 74 unrelated animals from four different breeds. Seven alleles were encountered. Linkage analysi s was performed in a large pedigree established for gene mapping. Link age between the IGF1 microsatellite and an anonymous microsatellite ma rker, S0005, was detected. Furthermore, IGF1 and S0005 was found to be linked to the porcine submaxillary gland mucin (MUC) gene, previously assigned to chromosome 5. The results presented here extend the linka ge group on pig chromosome 5 and are in accordance with conserved synt eny between human chromosome 12, cattle chromosome 5, mouse chromosome 10 and pig chromosome