Genetic variability of Lipoprotein lipase gene (LPL) and preliminary association study with milk fatty acids in Italian Mediterranean river buffalo

Lipoprotein lipase is a enzymatic glycoprotein responsible for hydrolysis of triacylglycerol cores (TG) of chyromicrons and low density lipoproteins. It is associated with the luminal side of capillaries and arteries where it hydrolyzes TG to produce free fatty acids. These free fatty acids are assimilated by muscle and adipose tissue. Therefore LPL regulate energy balance, fat deposition and growth traits. The gene coding for such protein has been deeply investigated in several species, including ruminants. For instance in bovine species the cDNA has been completely determined (Senda et al., 1987) and SNP were recently associated with milk fat content (Marchitelli et al., 2013). In goat a missense mutation at position 17 of the signal peptide has been associated with fat content and tended to affect the milk dry weight basis (Badaoui et al., 2007). Milk yield and composition are of great economic importance for the dairy industry of southern Italy where river buffalo is mainly reared for the cheese making as mozzarella PDO (Protected Denomination of Origin – Reg. EC 510/2006). The identification of genes associated with phenotypic differences for this trait could allow for the implementation of gene-assisted selection programs. The aim of this study was to characterize the LPL locus, to search for genetic markers and to test preliminary associations between the milk fatty acid content and the genetic variability in the Italian Mediterranean river buffalo.