Identification and characterization of polymorphisms within the 5' flanking region, first exon and part of first intron of bovine GH gene

Association of milk production traits with genetic variants in exon 5 and intron 3 of bovine growth hormone (bGH) gene in Sahiwal cattle

The main objective of this study was to determine the association of production traits with genetic variants in exon 5 and intron 3 of bovine growth hormone (bGH) gene in Sahiwal cattle. The analyses were based on the detection of single nucleotide polymorphisms (SNPs) in GH-AluI (exon 5) and GH-MspI (intron 3) using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. The frequency of AluI (L/V) and MspI (T/C) alleles were 86.20/13.70 and 89.80/9.50, respectively. The distribution of the frequency of GH genotypes for LL, LV, and VV were 73.4, 25.5, and 1.0 and for TT, TC, and CC genotypes were 80.9, 17.7, and 13.0, respectively. Season of calving had none but period of calving had significant effect on the studied production traits. The phenotypic data was adjusted for non-genetic factors and regression analysis was done. There was detectable significant effect of the GH-AluI and GH-MspI on the analyzed production traits. The cows with LL genotype had significantly higher milk yield traits than the LV genotype. Similarly, the productive performance of the studied cows with TT genotype was also significantly higher than TC and CC genotypes. Results revealed that the Sahiwal cows with LL and TT genotypes of the bGH locus can be considered to be a favourable genotype for production traits, although these findings need to be confirmed by further research before SNPs can be used in a marker assisted selection program by the animal breeder.

Novel InDels of GHR, GHRH, GHRHR and Their Association with Growth Traits in Seven Chinese Sheep Breeds

The GH growth axis plays an important role in the growth and development of animals and runs through the whole life of animals. Many studies have shown that molecular mutations in key genes of the GH axis will affect the growth and development of animals. The purpose of this study was to explore the distribution characteristics of InDels of GHR, GHRH, and GHRHR in seven Chinese sheep populations, and to further explore the relationship between InDels and sheep growth traits. GHR showed high variation in Chinese sheep, and GHR-53 showed the highest minimum allele frequency (MAF). There was only one InDel mutation site in both GHRH and GHRHR. The genotype frequencies of Hu sheep (HS), Tong sheep (TS), and Lanzhou fat-tail sheep (LFTS) were quite different from other breeds. The association between GHR, GHRH, and GHRHR InDels and body size traits in seven varieties were analyzed. The results showed that there was no significant relationship between GHRH and body size traits in the seven sheep populations. There was a positive association between GHR-21 and hip height of LFSH (p < 0.05). GHR-43 reduced body height and chest depth of Small tail han sheep (STHS) and hip width of TS. GHR-44 significantly affected the body weight of HS, the body height of STHS and the head depth of TS. GHR-53 significantly reduced cannon girth of HS, chest of STHS and forehead width of TS. GHRHR-2 significantly reduced the body weight of LFHS. To sum up, this study revealed the effects of GHR, GHRH, and GHRHR InDels on sheep phenotypic traits, which indicated their potential application prospects in the genetic improvement of mutton sheep.

Association of lactation persistency with genetic variants of bovine growth hormone gene in Indian Sahiwal cows

The aim of this study was to determine the associations of persistency with genetic variants of bovine growth hormone (bGH) gene in Indian Sahiwal cows. The data pertaining to the monthly test day milk yield (MTDMY) and first lactation length (FLL) of 305 lactating Sahiwal cows over a period of 23 years (1993–2016) were subjected to analysis. Persistency of milk yield was estimated by using test day based ratio method and Wilmink b function. Mean LL was 220.06±8.15 days in all studied Sahiwal cows, however, 276.67±10.25 days in cows with ≥100 days of LL and having 500 kg MY. The peak of milk yields was achieved at third TD of the first lactation. Macrophage stimulating protein 1 (MspI) and Arthrobacter luteus1 (AluI) restriction endonucleases were used to digest the amplified regions in intron 3 and exon 5, respectively of bGHgene. The bGHMspI restriction fragment length polymorphism (RFLP) yielded TT, CT and CC genotypes, whereas bGH-AluIRFLP yielded CC, CG and GG genotypes. Significant association was found between first lactation persistency estimated using test day based ratio method and bGH-MspI polymorphism. No significant association was found between first lactation persistency and bGH-AluI polymorphism. In summary, results of present study revealed that the TT genotype of bGH–MspI gene in Sahiwal cows has better lactation persistency than other genotypes.

Polymorphisms of the growth hormone gene and their association with growth traits and sex in Sarcocheilichthys sinensis

The growth hormone gene (gh) of Sarcocheilichthys sinensis was cloned and characterized in this study. The cDNA length of gh was 973 bp, containing a 5'-UTR of 15 bp, a 3'-UTR of 325 bp and an open reading frame of 633 bp. The genomic DNA of gh was 2135 bp in length containing five exons and four introns. The precursor peptide of gh contained 210 amino acids (aa), including a signal peptide of 22 aa (Met¹-Ala²²) and a mature region of 188 aa (Ser²³-Leu²¹⁰). The similarity and identity ranges of the gh precursor peptide with those of other cyprinids were 88.6%-99.0% and 84.8%-98.6%, respectively. The gh of S. sinensis expressed at the highest level in the pituitary, and its expression was also detected in muscle and brain. Six polymorphic sites were detected in intron 1 (g.51InDel, g.64InDel and g.242InDel), intron 2 (g.864T>C), intron 3 (g.1017InDel) and intron 4 (g.1541A>G). Among these sites, g.242InDel was significantly associated with condition factor, g.1541A>G was associated with all six growth traits, while g.864T>C was associated with sex. The data obtained herein provide useful information for further studies on the regulation mechanisms of growth and sexual growth differences in S. sinensis.

Identification of Single Nucleotide Polymorphisms (SNPs) of the Bovine Growth Hormone (bGH) Gene Associated with Growth and Carcass Traits in Hanwoo

The purpose of this study was to find any association of the bovine growth hormone (bGH) gene with growth and carcass quality traits in Korean native cattle, Hanwoo. Genomic DNA was extracted from 21 Hanwoo individuals, and the 47 to 2,528 bp region of the bGH 2,856 bp (GenBank accession number M57764) including the promoter and the five exons was sequenced. A total of ten bGH SNPs were confirmed, including four (253 C>T, 303 C>T, 502 C>T, and 559 G>A) in the promoter, one (679 C>T) in exon 1, one (1,692 T>C) in intron 3, and four (2141 C>G, 2258 C>T, 2277 C>T, and 2291 A>C) in exon 5. The ten bGH SNPs were genotyped for a sample of 242 Hanwoo steers and association tests were performed to find any significant SNP that was correlated with growth and carcass quality. Of the SNPs, the 303 C>T SNP in the promoter region was significantly associated with 6-month-old weight, the 559 G>A SNP with longissimus dorsi muscle area, the 2141 C>G SNP in exon 5 with daily weight gain, and the 2258 C>T SNP with daily weight gain and carcass weight (p<0.05). The significant SNPs need to be verified in other Hanwoo populations before considering implementation of marker-assisted selection for genetic improvement of growth and carcass quality in Hanwoo.

Polymorphisms in growth hormone gene and their associations with calf weight in Japanese Black cattle

The objectives of this study were to detect effective genetic polymorphisms of bovine growth hormone (bGH) gene associated with calf weight in Japanese Black cattle. Fifty-eight sires and 47 breeding cows were used to detect the polymorphisms in exons by single-strand conformation polymorphism (SSCP). Four homozygous and six heterozygous SSCP genotypes were identified in exon 5. Although each single nucleotide polymorphism (SNP) had been reported, these genotypes were caused by three SNPs at the nucleotide positions 2141, 2277 and 2291. Four haplotypes C-C-A, G-C-A, C-C-C and G-T-A were newly identified. It was suggested that other haplotypes not detected in this study may not exist, considering the allele frequencies reported in Bos taurus and Bos indicus, and the migrating process of native Japanese cattle. Thereafter, we examined associations between the detected polymorphic sites in exon 5 by PCR - restriction fragment length polymorphism and calf weight using 53 breeding dams and 135 calves. The birth weights of calves with haplotype G-C-A are significantly lighter and calves' weights produced by cows with such haplotype are also lighter at 30 days old, using regression analysis. Although further research is necessary, these results may serve as a useful criterion to select breeding stocks, especially in maternal abilities.