Investigation on muscle fatty acid composition in Italian Large White pigs and association study with ACACA, ACLY, SCD and FASN genes

P020 Investigation on muscle fatty acid composition in Italian Large White pigs and association study with ACACA, ACLY, SCD and FASN genes Roberta Davoli1 , Martina Zappaterra1 , Anna Maria Belmonte2 , Giovanna Minelli2 , Paolo Macchioni1 , Paolo Zambonelli1 1 Dipartimento di Scienze e Tecnologie Agroalimentari (DISTAL), Alma Mater Studiorum University of Bologna, Italy 2 Dipartimento di Scienze della Vita, University of Modena and Reggio-Emilia, Reggio Emilia, Italy Contact: roberta.davoli@unibo.it In recent years, a growing awareness of the association between diet and health has led nutritional quality to become a relevant factor in consumers’ food choices, in particular, meat products with lower omega-6 to omega-3 ratio and enriched in omega-3 polyunsaturated fatty acids (PUFA) are preferred. However, consumers’ dietary demands and technological requirements by the meat industry do not completely match: PUFA are more likely to incur in lipolytic and oxidative processes than saturated fatty acids (SFA), causing rancidity, abnormal flavours, fat softness and altered organoleptic properties of pork and dry-cured hams. The aim of this research is the identification of genetic associations between muscle fatty acid (FA) composition and candidate genes related to fat metabolism. DNA extraction was performed using Semimembranosus muscle samples of 430 Italian Large White pigs. FA composition was determined by capillary gas-chromatography and backfat thickness (BFT) was measured by calibre on the median line of each carcase. Single Nucleotide Polymorphisms (SNPs) in Fatty Acid Synthase (FASN), StearoylCoA Desaturase Delta-9 (SCD), Acetyl-CoA Carboxylase Alpha (ACACA), and Fatty Acid Synthase (ACLY) genes were utilised for this research. Statistical analyses were carried out using the MIXED procedure of SAS 9.4 considering sex, slaughtering day and genotype of the analysed SNPs as fixed effects; BFT was considered as covariate; sire effect was included as random factor. The p values were corrected using the adjusted-FDR values calculated by SAS MULTTEST procedure. Contrasts among the estimated least square means were calculated using the Tukey–Kramer test. Additive and dominant effects were obtained by t-test. Considering the adjusted p values, FASN and SCD SNPs resulted significantly associated with FA composition. FASN TT genotype showed an association with the content of C12 and C14 saturated FAs, in agreement with the biological role of this enzyme in the FA chain elongation. SCD TT genotype shows the highest monounsaturated FA content in agreement with the biological role of SCD enzyme in FA desaturation. The detected association between SNPs and parameters of fatty acid composition, once validated, could be useful to improve the knowledge of genes affecting pork FA composition. Acknowledgements The research was funded by ProSuIT project (AGER- Fondazione CARIPLO) and PRIN 2015 national project [no. 201549TZXB001].