A 5'UTR SNP of GHRHR locus is associated with body weight and average daily gain in Chinese cattle

The polymorphism of the ovine insulin like growth factor-2 (IGF2) gene and their associations with growth related traits in Tibetan sheep

In the current study, the role of the ovine IGF2 as a potential candidate gene was investigated as though marker-assisted selection in Chinese Tibetan sheep. The Sanger DNA sequencing method explored five single nucleotide polymorphisms (SNPs) in 5'UTR of the ovine IGF2 gene (C15640T, G15801A, G15870A, C15982G and G15991A) in Chinese Tibetan sheep. The frequencies of four SNPs were within the Hardy-Weinberg Equilibrium (chi-square test) except C15982G. The statistical analysis indicated that the C15640T and G15801A were significantly associated with body height, body length, chest circumference, and body weight (P < 0.05 or P < 0.01). Furthermore, C15982G variant exhibited significant correlation with the body weight (P < 0.01). These findings suggests that the promoter variants of IGF2 gene could be used as a candidate gene through marker-assisted selection for the body weight and body measurement traits in Tibetan sheep breeding program.

Polymorphisms of the Growth Hormone Releasing Hormone Receptor Gene Affect Body Conformation Traits in Chinese Dabieshan Cattle

This study was performed to expose the polymorphisms of the growth hormone-releasing hormone receptor gene in Chinese Dabieshan cattle, evaluate its effect on body conformation traits, and find potential molecular markers in Chinese cattle. The GHRHR structure and the phylogenetic tree were analyzed using bioinformatics software. The polymorphism of the GHRHR gene in 486 female cattle was genotyped by PCR-RFLP and DNA sequencing, and the association between SNPs and body conformation traits of Chinese Dabieshan cattle was analyzed by one-way ANOVA in SPSS software. GHRHR was often conserved in nine species, and its sequence of cattle was closest to sheep and goats. Six polymorphic SNPs were identified, g.10667A > C and g.10670A > C were missense mutation. The association analysis indicated that the six SNPs significantly influenced the body conformation traits of Chinese Dabieshan cattle (p < 0.05). Six haplotypes were identified and Hap1 (-CAACGA-) had the highest frequency (36.10%). The Hap3/5 (-GCCCCCGGAAGG-) exhibited a significantly greater wither height (WH), hip height (HH), heart girth (HG), and hip width (HW) (p < 0.05). Overall, the polymorphisms of GHRHR affected the body conformation traits of Chinese Dabieshan cattle, and the GHRHR gene could be used as a molecular marker in Dabieshan cattle breeding programs.

Single nucleotide polymorphisms in the growth hormone receptor gene and Alu1 polymorphisms in the diacylglycerol acyltransferase 1 gene as related to meat production in sheep

Aim:

This study aimed to investigate the polymorphisms in genes related to meat production, including growth hormone receptor (GHR) and diacylglycerol acyltransferase 1 (DGAT1) genes, in different breeds of sheep, including Barki, Najdi, and Harri.

Materials and Methods:

Blood samples were collected from 75 randomly selected healthy Barki, Najdi, and Harri breeds of sheep, with 25 samples per breed. GHR and DGAT1 genes were identified using a single nucleotide polymorphism assay followed by digestion with the restriction enzyme Alu1.

Results:

The analysis of the GHR gene sequence showed nucleotide substitutions at nt 69 in exon 10 (c.69 G > A); this mutation is considered a transition mutation. The sequences of detected SNPs in the GHR gene in the different sheep breeds were submitted to the GenBank database with accession numbers MG906773 to MG906781. The substitutions at exon 10 (c.69 G > A) results in an alteration to the amino acid (p. Lysine > Arginine). At c.69, the A allele frequency was 0.61, 0.59, and 0.54, while the G allele frequency was 0.39, 0.41, and 0.46, for Barki, Najdi, and Harri breeds, respectively. The genotype AG at nt 69 locus had the highest frequency in the Najdi and Harri sheep. The frequency of AG was 0.62, 0.61, and 0.64, while the frequency of AA was 0.30, 0.28, and 0.22, for Barki, Najdi, and Harri sheep, respectively. After digestion with the restriction enzyme AluI, the DGAT1 locus had two genotypes, CC and CT. The highest frequency, 0.88, was found for allele C, which was detected in Barki breed. The lowest frequency, 0.75, for the same allele was found for Harri.

Conclusions:

The detected CT genotype may explain the moderate intramuscular fat content and muscle marbling in the Barki sheep breed.

Associations between genetic variants of the POU1F1 gene and production traits in Saanen goats

This study was conducted to determine the polymorphisms of the POU1F1 gene and their relationships with milk yield and components, litter size, birth weight, and weaning weight in goats. For this purpose, a total of 108 Saanen goats from two different farms (Bornova and Manisa) were used as animal materials. Polymorphisms at the exon 6 and the 3' flanking region of the POU1F1 gene were determined by using PCR-RFLP with PstI and AluI restriction enzymes and DNA sequencing analyses. Two alleles and three genotypes were identified by AluI or PstI digestions of the POU1F1 gene. The genotypes frequencies of TT, TC, and CC were 64.8 %, 31.5 % and 3.7 % for the PstI locus; 54.6 %, 31.5 % and 13.9 % for the AluI locus, respectively. T allele frequencies (0.56 and 0.88 for the AluI locus, 0.80 and 0.81 for the PstI locus, respectively) were predominant in both loci at the Bornova and Manisa farms. In terms of POU1F1-AluI and POU1F1-PstI loci, two populations were found to be in Hardy-Weinberg equilibrium. In the POU1F1-AluI locus, significant associations were found between genotypes and lactation milk yield and litter size. Similarly, a significant relationship between genotypes and birth weight in the POU1F1-PstI locus ( p < 0.05 ) was determined. The TC and CC genotypes were observed to be higher than the TT genotype for lactation milk yield and litter size at the POU1F1-AluI locus. Birth weight was found to be higher in animals that have the CC genotype at the POU1F1-PstI locus. In conclusion, the POU1F1 gene can be used as a molecular marker for economic features like reproduction, growth, milk content and yield in Saanen goats.