Backfat thickness in pigs is positively associated with leptin mRNA levels

The obese (ob) gene isolated from ob/ob mice in 1994 is expressed specifica lly in adipose tissue. The gene product, leptin, regulates food intake, ene rgy expenditure and puberty. Reported herein is a 2477 bp mRNA sequence for the pig obese gene, which includes the complete coding sequence. Two diffe rent ob cDNAs were identified, which differed by the inclusion or exclusion of a single glutamine codon at position +49 of the protein sequence. The p ig obese gene encodes a 4.5 kb mRNA transcript, which is specific to adipos e tissue. Southern blot analysis of fat and lean pigs showed a DNA polymorp hism related to the lean phenotype. Differences in leptin mRNA levels showe d that fat pigs have a higher level of leptin mRNA than lean pigs. These fi ndings indicate that pig leptin expression can be associated with subcutane ous fat accumulation in pigs.