A relationship between the PCR-RFLP polymorphism in porcine MYOG, MYOD1 and MYF5 genes and microstructural characteristics of m. longissimus lumborum in Pietrain × (Polish Large White × Polish Landrace) crosses

Abstract

Muscle fibre formation takes place during embryonic development and is regulated by the MyoD gene family, which consists of four genes, MYOD1, myogenin, MYF5 and MRF4. A relationship was studied between MYOD1, myogenin and MYF5 genotypes and microstructural characteristics of the m. longissimus lumborum in pigs – crosses: Pietrain × (Polish Large White × Polish Landrace). The data included 115 unrelated animals slaughtered at about 105 kg live body weight. Within 45 min after exsanguination, samples were taken from the m. longissimus lumborum, frozen in liquid nitrogen and later analysed for the diameter of slow-twitch oxidative, fast-twitch oxidative and fast-twitch low-oxidative fibres, their proportion in a bundle, the proportion of pathological changes and number of fibres per unit area. The RYR1 and MyoD genotypes were determined using the PCR-RFLP technique. A significant or highly significant relation was observed between the diameter of all types of muscle fibres and genotype RYR1 – the highest values were recorded for homozygotes TT (genetically stress-sensitive). A relation between MyoD genotypes and microstructural characteristics of the m. longissimus lumborum was analysed on a group of 93 animals of the genotype CC or CT at locus RYR1. Sex appeared to have no significant effect on the muscle microstructural traits in this group of animals. The content of fast-twitch oxidative fibres (FTO) was significantly related to the MYF5 genotype, whereas that of fast-twitch low-oxidative fibres (FT) was affected by the MYOD1 and MYF5/DdeI genotypes. The proportion of angular fibres in a bundle was related to MYF5/HinfI genotype. The results showed that MyoD genes could be considered as candidate genes for some microstructural characteristics of m. longissimus lumborum in pigs.  

Lack of an association between a single nucleotide polymorphism in the bovine myogenic determination 1 (MyoD1) gene and meat quality traits in indigenous Chinese cattle breeds

“…Myogenesis and postnatal tissue growth are determined by the muscle-regulatory factor gene family (MyoD1), comprised of four genes (MyoD1, MYF4, MYF5, and MYF6). Their mutations have been described in several pig breeds and pig lines to affect the meat loosening in the carcass (Cieslak et al, 2002;Kuryl et al, 2002) and the micro-structural features of muscle tissue (Klosowska and Fiedler, 2003;Klosowska et al, 2001Klosowska et al, , 2004. Nevertheless, there have been very few studies on the MyoD1 gene in cattle.…”

Histological characteristics of the musculus longissimus lumborum et thoracis muscle fibres in pigs in relation to selected RYR1, MYOG, MYOD1 and MYF6 genotypes

“…Regarding the influence of the MYOD1 gene, Lee et al (2012) concluded that individual genotypes have a significant effect on different types of muscle fibre characteristics. It was demonstrated, in accordance with Klosowska et al (2004), that the CC genotype in type IIB is associated with higher number of muscle fibres with a smaller area and diameter. Klosowska et al (2004) further inform about a significant effect of the MYOD1 gene on the proportion of fast glycolytic white (IIB) fibres.…”

Associations between newly discovered polymorphisms of the Myod1 gene and body parameters in Stavropol breed rams

“…A positive correlation between the level of expression of MyoD1 and the cold carcass yield was found in sheeps (Lobo et al, 2012). A polymorphism of MyoD1 gene in pigs is associated with meat quality (Klosowska et al, 2004;Kapelanski et al, 2005;Liu et al, 2008), including fatness (Kuryl et al, 2002) and meat marbling (Verner et al, 2007). In chickens, a mutation in both MyoD1 and Mrf4 genes was associated with an increase in the diameter of muscle fibres.…”