Effect of DGAT1 polymorphisms on the estimated breeding values of Czech Simmental sires

Abstract

ABSTRACT:The aim was to evaluate the effect of polymorphisms in the promoter and in the coding region of the DGAT1 gene on the estimated breeding values (EBV) of Czech Simmental sires. The K232A polymorphism (n = 191) in the coding region was genotyped by PCR/RFLP, and the KU and SA polymorphisms in the promoter (n = 203) were identified in an automatic sequencer. In the K232A polymorphism, the frequency of the genotype AA (Alanine) was greater than that of the genotype KA, the homozygous genotype KK (Lysine) was not found. Similarly, the allele A predominated over the K allele (0.945 and 0.055). The EBV for milk performance have been assigned to the genotypes, and the associations quantified. For the AA genotype and A allele, positive association with EBV of milk yield and protein yield was found, and negative association with the breeding values of fat percentage and yield, and protein percentage, but only the value of fat content was found to be significant. The positive non-significant association of the A variant with the protein yield was caused by the high milk yield. In the KU polymorphism, the CC genotype was associated significantly with lower EBV for the fat percentage, both the C allele and the CC genotype were associated with higher EBV for milk yield, so both the fat and the protein yield were non-significantly increased. For the diplotypes K232A/KU, there was a significant association with the fat percentage. The AACC combination seemed to have some breeding potential. The K232A polymorphism explained maximum of 6.2% of EBV variability, the KU polymorphism of 4.4%, and the SA polymorphism of 4.2%. The diplotypes K232A/KU explained maximum of 7.4% of variability. The highest proportion of variability was explained for fat percentage. The results confirmed the important role of the BTA14 region in controlling milk performance.

Effect of DGAT1, FASN and PRL genes on milk production and milk composition traits in Simmental and crossbred Holstein cattle

“…The effects of the genotypes on lactation traits showed that in crossbred Holstein the KA genotype had a significantly higher fat content than the AA genotype (P <0.05) (Table 2). These results were in accordance with the findings of other authors (Molee et al 2012, Hanusova et al 2014, Kadlecova et al 2014) who reported that the K allele is responsible for variations in the amount of milk fat.…”

“…In both groups, regarding DGAT1 gene, the genotype KA prevailed over both homozygous genotypes with allele K as less frequent (Table 1). The results from the current study differed from those reported in a previous study for the Simmental breed, where the frequency for the allele K was 0.055 (Hanusova et al 2014). Results for crossbred Holstein were in accordance with earlier findings (0.36) (Molee et al 2012) and Holstein (0.28) (Kadlecova et al 2014).…”

Associations between gene polymorphisms, breeding values, and glucose tolerance test parameters in German Holstein sires

“…But there are opportunities to use clinical diseases in addition to predictor traits and genomic information to strengthen genetic evaluations for metabolic health in the future. The analysis of the relationship between polymorphic genes and EBVs for milk performance (Table 3) showed that DGAT1 was significant consistently with the previous observations by Grisart et al (2002) and Hanusova et al (2014). The GC/GC genotype (GC coding for alanine) was associated with high milk yield like in the previous reports.…”

Effect of DGAT1 gene variants on milk quantity and quality in Holstein, Simmental and Brown Swiss cattle breeds in Croatia

“…The gene diacylglycerol-O-transferase 1 (DGAT1) is mapped in the centromere region of BTA14 and encodes the diacylglycerol-O-transferase enzyme which catalyses the final step in triglyceride synthesis (Grisart et al, 2002). The allele frequencies and effects of polymorphic variants of DGAT1 gene have been characterized in many dairy cattle population: in New Zealand (Spelman et al, 2002), Germany (Thaller et al, 2003), France (Gautier et al, 2007), Italy (Scotti et al, 2010), Czech Republic (Hanusova et al, 2014) and many other countries. In dairy cows, DGAT1 gene is considered to be a candidate gene for milk fat content.…”