DGAT1 is a microsomal enzyme that catalyses the final step in triglycerides 
synthesis. DGAT1-deficient mice are viable, lean, fertile and resistant to diet 
induced obesity. We have previously identified a quantitative trait loci (QTL) 
on chromosome 4 that affects fatty acid composition in an F2 cross between 
Iberian x Landrace. The human DGAT1 gene is located on chromosome 8q24.3, this 
region aligns to porcine chromosome 4, making the pig DGAT1 gene a suggestive 
positional candidate gene for the QTL. In this study, we sequenced 1679 bp of 
the mRNA from animals of five pig breeds (Iberian, Landrace, Large White, 
Piétrian and Meishan) to identify genetic variants. One of the polymorphisms 
found creates a polymorphic HinfI restriction site and it was genotyped by 
PCR-RFLP in these five pig breeds. Allele A was not found in the analysed 
Iberian and Landrace populations, whereas Meishan population presents the 
highest frequency (35%). The DGAT1 gene was located by radiation hybrid mapping 
to the porcine chromosome 4, outside the confidence interval for the fatty acid 
composition QTL and excludes it as a positional candidate gene.