Porcine granulin gene (GRN): molecular cloning, polymorphism and chromosomal localization.

GRN has been shown to have roles in multiple processes involved in cell growth, development and wound repair in rodents and humans. We have isolated the full-length cDNA of GRN gene encoding porcine granulin protein by in silico cloning, RT-PCR and RACE. The deduced amino acid indicated 71.5% identity with the corresponding human sequence and the seven and one-half granulins showed highly conservative between pig, human and murine. A single nucleotide substitution resulting in the amino acid change (ATG/Met --> TTG/Leu) was detected within exon 5. Allele frequencies in six pig breeds showed distinctive differences between those Chinese indigenous pig breeds and European pigs. Using the IMpRH panel, we mapped the porcine GRN gene to porcine chromosome 12p11-p13. Our data provide basic molecular information useful for the further investigation on the function of GRN gene.