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Association of growth hormone (GH) and Prolactin (PRL) genes polymorphism with milk production trait in Polish Black-and-White cattle

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Associations were analysed between polymorphisms localized in intron 3 of the growth hormone gene (GH-MspI) and exon 3 of the prolactin gene (PRL-RsaI) and milk production traits of Black-and-White (Polish Friesian) cattle, including a total of 1086 cows. PCR-RFLP method was used for identification of genotypes. The following frequencies of genotypes and alleles were found: GH – 0.766, 0.215 and 0.019 for +/+, +/-and-/-, respectively, and 0.873 and 0.127 for GH + and GH-, respectively; PRL – 0.734, 0.257 and 0.009 for AA, AB and BB, respectively, and 0.862 and 0,138 for PRL A and PRL B , respectively. Significant differences between the herds were observed in the frequencies of both genotypes and alleles. In all three lactations the GH +/+ cows yielded most milk, whereas +/-cows showed higher milk fat content than +/+ individuals. AA cows of the PRL gene showed higher milk protein content than AB individuals. KEY WORDS: cattle / growth hormone / PCR-RFLP / polymorphism / prolactin / milk production Bovine growth hormone (bGH) is a single peptide of about 22-kDa molecular weight [23]. It is composed of 190 or 191 amino acids, containing Ala or Phe at the N-terminus, due to alternative processing of bGH precursors [18, 24]. Moreover, Leu or Val amino acid substitutions at residue 127 exist due to the allelic polymorphism [21].
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... As reviewed up to now, the bovine PRL gene is located in the 23 rd chromosome. It spans about 10 kb (9.4 kb), including here five exons and four introns (Dybus 2002;Wojdak-Maksymiec et al 2008;Sodhi et al 2011;Alfonso et al 2012;Sonmez & Ozdemir 2017;Thuy et al 2018;Oğuzkan & Bozkurt 2019). It was firstly mapped by Hallerman et al (1988), as reviewed by Alipanah et al (2007b) and He et al (2006), its content in exons and introns being reported by Camper et al (1984), as reviewed by Dybus (2002). ...
... It spans about 10 kb (9.4 kb), including here five exons and four introns (Dybus 2002;Wojdak-Maksymiec et al 2008;Sodhi et al 2011;Alfonso et al 2012;Sonmez & Ozdemir 2017;Thuy et al 2018;Oğuzkan & Bozkurt 2019). It was firstly mapped by Hallerman et al (1988), as reviewed by Alipanah et al (2007b) and He et al (2006), its content in exons and introns being reported by Camper et al (1984), as reviewed by Dybus (2002). Moreover, Patel & Chauhan (2017) reported the location of the bovine PRL gene at 43 cM close to the chromosomal QTL. ...
... Similarly, in Red Pied Russian cattle, the BB genotype yielded more protein than the AA genotype and the latter yielded more than the AB genotype. The AA genotype was associated with higher milk protein content than AB in Black and White cattle (Polish Friesian) (Dybus 2002), while the BB genotype had the highest somatic cell count and AA the lowest in a study performed in Red and White Holstein Friesian cattle by Wojdak-Maksymiec et al (2008). ...
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The prolactin (PRL) gene, mapped on chromosome 23 in cattle, is usually considered in association studies with various milk traits. Although contradictory results of genotypes associations can be reported, they are generally justified if taking into account the variability of individuals (differences in investigated breeds), the number of individuals, and the investigated milk trait. The PRL gene is not a part of any Quantitative Trait Locus (QTL), but the gene of its receptor (PRLR) is. This fact is important, considering the role of PRLR protein in some steps of PRL action. This study is a review that debates important and updated aspects of PRL and PRLR genes' location and structure, physiological mechanisms of action of PRL hormone, and some associations of a well-studied polymorphism (a point mutation) with some milk traits.
... The meta-analysis for LMT trait indicated the superiority trend of genotypes may be in following order: AB = AA > BB. The superiority of AB and AA genotype over BB genotype for LMY was also reported by Dybus (2002) in Polish Black and White cattle, and Alipanah et al. (2008) in Black Pied cattle. Additionally, Ghasemi et al. (2009), Alfonso et al. (2012 and Oguzkan and Bozkurt (2019) reported AA as favorable genotype for milk production in Montebeliard, American Swiss and Holstein cattle, respectively. ...
... Our finding was in agreement with reports of Alipanah et al. (2008) in Black Pied and Red Pied cattle and Dybus et al. (2005) in Jersey cattle. However, this finding was contrary to reports of Dybus (2002) in Polish Black and White cattle, who reported non-significant difference between SNPs for this trait. On the basis of our finding, it may be suggested that B allele may be promoted in order to improve Fat% in dairy cows, but at the cost of reduction in milk yield. ...
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The present meta-analysis was carried to provide the more reliable estimates of gene frequency and association of Rsa 1 generated candidate genotype of prolactin gene within exon-3 with performance traits in 1198 Indian dairy cows using data from 15 published studies. Six genetic models viz., codominant (AA vs. AB, AA vs. BB and AB vs. BB), dominant (AA+AB vs. BB), completely over dominant (AA+BB vs. AB) and recessive (AA vs. AB+BB) were used to obtain standardized mean difference (SMD) between genotypes. Meta-analysis showed that the gene frequency of A allele (156 bp) was 0.60 (95% confidence interval (CI) 0.54, 0.65). In association analysis, cows with AB genotype [SMD = 0.65, 95% CI 0.00, 1.30] had significantly (P < 0.05) higher lactation milk yield (LMY) as compared to BB genotype, whereas AA and AB genotypes had similar trend. Likewise, AA + AB also had larger effect [SMD = 2.31, 95% CI 0.21, 4.10] on LMY as compared to BB. Cows with AB genotype had significantly lower age at first calving (AFC) with small effect [SMD (AA vs. AB) = 1.38, 95% CI 0.06, 2.70] and medium effect [SMD (AB vs. BB) = − 3.83, 95% CI − 6.41, − 1.24] as compared to cows with AA and BB genotypes, respectively. This finding was confirmed under dominant and completely over dominant models. In case of fat%, AA genotype showed negative effect (SMD = − 0.51, 95% CI − 0.84, − 0.17) under recessive model. It was concluded that the propagation of allele A is promising to help dairy farmers to improve the genetic quality of their dairy cows.
... Fourth, it is common for genes regulating the expression of milk yield to have a negative or positive correlation with milk composition (protein, fat, lactose and somatic cell count, among others). In this context, the Prolactin gene (PRL), which encodes for a physiological multi-function hormone, whose specific actions occur at the reproductive and lactation levels, and, hence, influences milk yield and milk protein and fat percentages [120]. In the same way, the Prolactin Receptor gene (PRLR), which encodes for a receptor associated with a wide range of endocrine functions, such as mammalian lactation and body growth, is one of the most frequently addressed candidate genes for milk traits in the literature, given its regulation of the expression of milk yield and lactose, protein and fat percentages [121]. ...
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Despite their pivotal position as relevant sources for high-quality proteins in particularly hard environmental contexts, the domestic goat has not benefited from the advances made in ge-nomics compared to other livestock species. Genetic analysis based on the study of candidate genes is considered an appropriate approach to elucidate the physiological mechanisms involved in the regulation of the expression of functional traits. This is especially relevant when such functional traits are linked to economic interest. The knowledge of candidate genes, their location on the goat genetic map and the specific phenotypic outcomes that may arise due to the regulation of their expression act as a catalyzer for the efficiency and accuracy of goat-breeding policies, which in turn translates into a greater competitiveness and sustainable profit for goats worldwide. To this aim, this review presents a chronological comprehensive analysis of caprine genetics and genomics through the evaluation of the available literature regarding the main candidate genes involved in meat and milk production and quality in the domestic goat. Additionally, this review aims to serve as a guide for future research, given that the assessment, determination and characterization of the genes associated with desirable phenotypes may provide information that may, in turn, enhance the implementation of goat-breeding programs in future and ensure their sustainability.
... Growth hormone axis governs the important functions related with regulation of metabolism, lactation and reproduction in farm animals. Growth hormone gene codes a 22 KDa single chain polypeptide protein primarily produced and secreted by the somatotrophs of the anterior pituitary gland in circadian and pulsatile manner (Dybus et al. 2002). Camel growth hormone gene is of size 1.9 kb, and found similar with other mammalian species consisting of 5 exons and 4 introns (Maniou et al. 2003). ...
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The present study was aimed to assess the genetic polymorphism of growth hormone (GH) gene in Jaisalmeri and Sindhi camels using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. Genomic DNA were isolated from venous blood samples collected from 93 Indian camels (Jaisalmeri-38 and Sindhi-55 camels) and 613-base pair fragment of GH gene was amplified from each genomic DNA sample by polymerase chain reaction. The PCR-RFLP was done using restriction enzyme MspI which revealed three genotypes, viz. CC, CT and TT in both the breeds. Our result indicated that both the breeds were polymorphic in nature. The corresponding genotype frequency in Jaisalmeri and Sindhi breeds were 0.474 and 0.345 for the CC, 0.395 and 0.564 for CT, 0.131 and 0.091 for TT genotypes and the corresponding C allele frequency was 0.671 and 0.627 and T allele frequency was 0.329 and 0.373. The CT genotype was found predominant in the Sindhi breed, whereas CC genotype was predominant in Jaisalmeri breed. The frequency of C allele was higher than the T allele in both of the breeds. These camel populations were in Hardy-Weinberg Equilibrium indicating that the populations meet the HWE assumptions and genetic variations were conserved. It could be concluded that Jaisalmeri and Sindhi camels having different genetic variants of GH gene might be investigated for production a DNA marker for growth and production traits in Indian camels.
... Many researchers (Alipanah et al., 2008;Maksymiec et al., 2008;Ghasemi et al., 2009) reported that the PRL gene is highly polymorphic and had an association with milk production traits. Particularly, PRL-Rsa1 locus had a significant effect on milk production and fat percentage in dairy cattle (Chung et al., 1996;Mitra et al., 1995;Chrenek et al., 1998;Udina et al., 2001;Dybus, 2001;Sacravarty et al., 2008;Wojdak et al., 2008). The genetic evaluations incorporating genomic information of late have been adopted in many countries in dairy animals. ...
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Background: The selection of genetically superior animals at an early stage of life, the molecular markers are used along with traditional selection. The study was carried out to identify the genetic polymorphism in the exon3 region of the Prolactin and enumerate its effect on milk production performance in Sahiwal cattle. Prolactin plays an imperative regulatory role in mammary gland development, milk emission and lactogenesis. Analysed the sequence of this gene to explore whether mutations in this sequence and it could be accountable for quantitative variations in milk production and its composition traits.Methods: Total DNA was isolated from the blood samples of 98 pedigreed Sahiwal population. Using PCR-RFLP method and direct sequencing, noticed a single-nucleotide polymorphism in exon3 region of the Prolactin gene in 156bp and also the effect of non- genetic factors on each trait was assessed by least-squares analysis for non-orthogonal data by a fixed model.Result: PCR-RFLP was done with RsaI restriction endonuclease for the identification of different genotypes. The frequency of G and A alleles of the Prolactin gene was evaluated as 0.575 and 0.425, whereas the frequencies of GG, GA and AA genotypes for the Prolactin gene were 0.45, 0.25 and 0.30, respectively. SNP (G55A) conferred an increase in test-day milk yield around 321.5g, in test day fat yield around 13.9g and in test day SNF yield increase was 19.4g, respectively. High correlation was perceived from test day (TD2) onwards between test day traits and lactation milk yield indicating that selection based on identified SNP in TD2 increased test day milk yield, fat yield and SNF yield by 1.1472 kg, 29.6gm and 45.4gm, respectively.
... It is necessary to select genotypes with high growth and meat quality for more contribution of camels to the agricultural economy (Ramadan and Inoue-Murayama, 2017). Growth hormone (GH) is an anabolic hormone which plays an important role in postnatal longitudinal growth, tissue growth, lactation, reproduction as well as protein, lipid and carbohydrate metabolism (Dybus, 2002;Daverio et al, 2012). Among the several candidate genes, growth hormone (GH) gene structure and its role in farm animals like cattle, buffalo, sheep and goat production is widely studied. ...
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... One of the most significant associations on chromosome 1 at 79 Mb was close to SST (somatostatin) and BCL6 (BCL6 transcription repressor). Since SST regulates the secretion of pituitary hormones including prolactin (Eigler and Ben-Shlomo, 2014), it may contribute to the regulation of milk production (Dybus, 2002;Alipanah et al., 2007). And BCL6 was found to be expressed in mammary epithelium and also in breast cancer (Logarajah et al., 2003). ...
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German Black Pied cattle (DSN) is an endangered population of about 2,550 dual-purpose cattle in Germany. Having a milk yield of about 2,500 kg less than the predominant dairy breed Holstein, the preservation of DSN is supported by the German government and the EU. The identification of the genomic loci affecting milk production in DSN can provide a basis for selection decisions for genetic improvement of DSN in order to increase market chances through the improvement of milk yield. A genome-wide association analysis of 30 milk traits was conducted in different lactation periods and numbers. Association using multiple linear regression models in R was performed on 1,490 DSN cattle genotyped with BovineSNP50 SNP-chip. 41 significant and 20 suggestive SNPs affecting milk production traits in DSN were identified, as well as 15 additional SNPs for protein content which are less reliable due to high inflation. The most significant effects on milk yield in DSN were detected on chromosomes 1, 6, and 20. The region on chromosome 6 was located nearby the casein gene cluster and the corresponding haplotype overlapped the CSN3 gene (casein kappa). Associations for fat and protein yield and content were also detected. High correlation between traits of the same lactation period or number led to some SNPs being significant for multiple investigated traits. Half of all identified SNPs have been reported in other studies, previously. 15 SNPs were associated with the same traits in other breeds. The other associated SNPs have been reported previously for traits such as exterior, health, meat and carcass, production, and reproduction traits. No association could be detected between DGAT1 and other known milk genes with milk production traits despite the close relationship between DSN and Holstein. The results of this study confirmed that many SNPs identified in other breeds as associated with milk traits also affect milk traits in dual-purpose DSN cattle and can be used for further genetic analysis to identify genes and causal variants that affect milk production in DSN cattle.
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