A polymorphism in the stearoyl-CoA desaturase gene promoter influences monounsaturated fatty acid content of Duroc × Iberian hams

Data on 74 dry-cured hams from Duroc × Iberian pigs were used to examine whether the tag polymorphism AY487830:g.2228T>C in the promoter region of the stearoyl-CoA desaturase [SCD] gene affect fat desaturation and monounsaturated fatty acid (MUFA) as previously described in purebred Duroc hams. Samples were taken from sliced trays of dry-cured hams marketed as Jamón Ibérico de cebo, which were randomly purchased from the same supplier in different stores of the same supermarket chain. Genomic DNA was isolated from each sample to genotype for SCD and gender. Also, a sample of two slices was used to determine fat content and fatty acid (FA) composition by gas chromatography. The effect of the genotype (TT and CT) and gender (barrows and gilts) was estimated under a Bayesian setting. Results showed that the SCD polymorphism was associated to fat composition but not to fat content, with TT hams showing increased C18:1n-7, C18:1n-9, C20:1n-9 and MUFA (probability between 0.92-0.98) and decreased C18:2n-6, C20:4n-6 and polyunsaturated FA (PUFA) (probability between 0.91-0.99) as compared to the CT. As a result, the TT hams had more MUFA (0.95%) and a higher MUFA/PUFA ratio (0.43) than the CT. Barrows had more saturated FA (SFA) and less PUFA than gilts. No differences in MUFA content were found between genders. The SCD polymorphism had a greater impact on MUFA than using hams from barrows instead of gilts. It is concluded that the SCD polymorphism is a good tool to increase MUFA and MUFA/PUFA ratio in Duroc crossbred dry-cured hams. Additional key words: dry-cured ham; fatty acid composition; genetic marker; meat quality; pigs. Abbreviations used: B (barrows); CT (heterozygous genotype for the polymorphism AY487830:g.2228T>C); DM (dry matter); FA (fatty acids); G (gilts); IMF (intramuscular fat); MCMC (Markov chain Monte Carlo); MUFA (monounsaturated fatty acids); PUFA (polyunsaturated fatty acids); SCD (stearoyl-CoA desaturase); SE (standard error); SNP (single nucleotide polymorphism); SFA (saturated fatty acids); TT (alternative homozygous genotype for the polymorphism AY487830:g.2228T>C). Citation: Henriquez-Rodriguez, E.; Tor, M.; Pena, R. N.; Estany, J. (2015). A polymorphism in the stearoyl-CoA desaturase gene promoter influences monounsaturated fatty acid content of Duroc × Iberian hams. Spanish Journal of Agricultural Research, Volume 13, Issue 4, e0404, 8 pages. http://dx.doi.org/10.5424/sjar/2015134-8323. Received: 16 Jul 2015. Accepted: 13 Nov 2015. Copyright © 2015 INIA. This is an open access article distributed under the terms of the Creative Commons Attribution-Non Commercial (by-nc) Spain 3.0 Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Funding: Spanish Ministry of Economy and Competitiveness (MINECO, grant AGL2012-33529). EHR is recipient of a PhD scholarship from the University of Lleida. Competing interests: Three of the authors (JE, MT, and RNP) are named on the patent ES 2452791 B1 filed by University of Lleida on the use of markers of SCD for marker-assisted selective breeding in pigs. Correspondence should be addressed to Joan Estany: [email protected]