Effect of the calpain small subunit 1 gene (CAPNS1) polymorphism on meat quality traits in sheep

The aims of this study were to investigate the polymorphism in the calpain small subunit 1 gene (CAPNS1) and evaluate the associations of this gene's variants with meat quality traits in Coloured Polish Merino sheep. A 190-bp fragment of exons 5 and 6 including intron region of the CAPNS1 gene was amplified and subjected to MSSCP method to screen for polymorphisms. Traits of interest for this study were: muscle pH 24 h post mortem, reflectance coordinates (L*, lightness; a*, redness; b*, yellowness), water content, intramuscular fat content, total protein content, water-holding capacity, Warner Bratzler shear force, drip loss, and cooking loss. Two C/T substitutions, one in intron 5 and one in exon 6, were found. Three alleles named A1, B1 and C1 and six CAPNS1 genotypes - A1A1, A1B1, B1B1, A1C1, B1C1 and C1C1 - were detected. The A1 allele and A1B1 genotype were predominant with the frequencies of 0.467 and 0.419, respectively. The CAPNS1 genotype was found to have highly significant (P = 0.006) and significant (P = 0.037 and P = 0.039) effects on natural drip loss, lightness and intramuscular fat content, respectively. The CAPNS1 gene variants also tended to associate (P = 0.056) with cooking loss. Results of this study confirmed that CAPNS1 gene could be considered as a candidate gene of meat quality traits in sheep and may affect lamb quality parameters.