A single nucleotide polymorphism in the promoter region of river buffalo stearoyl CoA desaturase gene (SCD) is associated with milk yield

An association study between the milk yield trait and the stearoyl-CoA desaturase (SCD)polymorphism (g.133A>C) in Italian Mediterranean river buffalo was carried out. A fullcharacterization of the river buffalo SCD promoter region was presented. Genotyping informationwas provided and a quick method for allelic discrimination was developed. The frequency of the Callele was 0·16. Test-day (TD) records (43 510) of milk production belonging to 226 lactations of 169buffalo cows were analysed with a mixed linear model in order to estimate the effect of g.133A>Cgenotype, as well as the effect of parity and calving season. The SCD genotype was significantlyassociated with milk yield (P=0·02). The genotype AC showed an over-dominance effect with anaverage daily milk yield approximately 2 kg/d higher than CC buffaloes. Such a difference representsabout 28% more milk/d. The effect of the genotype was constant across lactation stages. Thecontribution of SCD genotype (r2SCD) to the total phenotypic variance in milk yield was equal to 0·12.This report is among the first indications of genetic association between a trait of economicimportance in river buffalo. Although such results need to be confirmed with large-scale studies in thesame and other buffalo populations, they might offer useful indications for the application of MASprogrammes in river buffalo and in the future they might be of great economic interest for the riverbuffalo dairy industry.