The slaughter value of cattle and beef quality are influenced by many factors, which can generally be divided into antemortem (breed, sex, age, housing system, diet, preslaughter handling) and postmortem (post-slaughter processing, chilling temperature, packaging). Studies of many authors have shown that meat quality traits can be also influenced by the individual genetic background of an animal. Numerous studies have been conducted worldwide to determine the functions of various genes as well as polymorphisms with potential effects on fattening and slaughter value of cattle and on beef quality. This study reviews the most important research done on the associations of polymorphisms in the calpain, calpastatin and myostatin genes with carcass traits and beef quality. Knowledge about the genes and chromosome regions associated with desired meat quality characteristics may prove very helpful when selecting pairs for mating and estimating the breeding value of offspring, mainly because it is difficult to improve meat quality traits based on conventional selection methods due to their low heritability and polygenic regulation. Furthermore, meat quality evaluation is expensive and can only be carried out after slaughter.

The purpose of this study was to analyse polymorphisms of the CAPN1, CAST and MSTN genes and their association with the microstructure of the Musculus longissimus thoracis (MLT) and textural parameters in bulls of the Holstein-Friesian breeds, black-and-white variety. The polymorphisms at the three loci: in position 6536 of the 3'UTR region of the CAPN1 gene, in position 230 of intron 5 in CAST gene, and in position 371 of the promoter region of the MSTN gene were analysed. Given the inconsequential genetic diversity at the analysed CAPN1 and MSTN loci in the animal sample, it was considered unreasonable to perform further statistical analyses aimed at determining associations between polymorphisms in these positions and meat characteristics. Based on an analysis of the CAST gene polymorphism, a significant association with certain histological and textural parameters was identified.