%0 Journal Article
%T Impact of two myostatin (MSTN) mutations on weight gain and lamb carcass classification in Norwegian White Sheep (Ovis aries)
%A Inger A Boman
%A Gunnar Klemetsdal
%A Ola Nafstad
%A Thor Blichfeldt
%A Dag I V£żge
%J Genetics Selection Evolution
%D 2010
%I BioMed Central
%R 10.1186/1297-9686-42-4
%X The impact of two known MSTN mutations was examined in a field experiment with Norwegian White Sheep. The joint effect of the two MSTN mutations on live weight gain and weaning weight was studied on 644 lambs. Carcass weight gain from birth to slaughter, carcass weight, carcass conformation and carcass fat classes were calculated in a subset of 508 lambs. All analyses were carried out with a univariate linear animal model.The most significant impact of both mutations was on conformation and fat classes. The largest difference between the genotype groups was between the wild type for both mutations and the homozygotes for the c.960delG mutation. Compared to the wild types, these mutants obtained a conformation score 5.1 classes higher and a fat score 3.0 classes lower, both on a 15-point scale.Both mutations reduced fatness and increased muscle mass, although the effect of the frameshift mutation (c.960delG) was more important as compared to the 3'-UTR mutation (c.2360G>A). Lambs homozygous for the c.960delG mutation grew more slowly than those with other MSTN genotypes, but had the least fat and the largest muscle mass. Only c.960delG showed dominance effects.In Norwegian White Sheep (NWS), two myostatin (MSTN) mutations affecting conformation and fat classes are segregating: the 3'-UTR mutation creating an illegitimate microRNA site (c.2360G>A) that was identified in Texel sheep [1] and a frameshift mutation explained by a deletion of one base pair in nucleotide position 960 (c.960delG), identified in NWS [2]. While c.2360G>A reduces the level of circulating myostatin to approximately one third, c.960delG generates a completely non-functional protein.Initially, the aim of the current study was to investigate the effect of the c.960delG mutation on growth and carcass traits in NWS under ordinary commercial management conditions. NWS is a synthetic crossbreed, composed of the Dala, Rygja, Steigar and Texel breeds [3]. However, during the course of this experiment, an
%U http://www.gsejournal.org/content/42/1/4