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- Growth hormone AluI polymorphism analysis in eight Portuguese bovine breedsPublication . Reis, Clara; Navas, D.; Pereira, M.; Cravador, A.A total of 195 bulls of eight Portuguese beef cattle breeds (Alentejana, Arouquesa, Barros , Maronesa, Marinhoa, Mertolenga, Mirandesa and Preta) were genotyped for the GH AluI polymorphism by the polymerase chain reaction and restriction length polymorphism (PCRRFLP). The genotype and gene frequencies for each breed were determined and shown to be quite variable among the breeds. The overall gene frequencies for L and V were 0.759 and 0.241, respectively. The relation between the bGH-AluI polymorphism and growth performances was ascertained in 168 of the animals analysed. According to our results there is a significant association between the genotypes LL and LV of the bGH and the average live body weight of the animals of the breeds Alentejana, Marinhoa and Preta.
- Single-strand conformation polymorphism detection of exon 7 of beta-casein gene in “Churra da Terra Quente” Portuguese indigenous ovine breedPublication . Bastos, Estela; Cravador, A.; Varejão, M. C.; Chaves, R.; Guedes-Pinto, HenriqueMilk protein polymorphisms provide a powerful tool for the knowledge o their molecular biology and physichochemical properties. It is becoming increasingly recognised that genetic variation may offer a source of differentiation that can improve milk technology, including cheesemaking.
- Pit-1 gene HinfI polymorphism detection in eight Portuguese bovine breedsPublication . Reis, Clara; Cravador, A.O nosso objectivo foi detectar o poliformismo HinfI do gene Pit-1 nas oito principais raças bovinas autóctones portuguesas.
- Single-strand conformation polymorphism (SSCP) analysis of exon 4 and exon 5 of growth hormone gene in “Serrana Transmontana” goat breedPublication . Varejão, M. C.; Bastos, Estela; Chaves, R.; Cravador, A.; Azevedo, Jorge; Guedes-Pinto, HenriqueThe origin of Serrana goat breed is lost in time: however the wild goat Capra pyrenaica, from the Serra da Estrela, is probably its ancestor. The Serrana is the most representative of Portuguese breeds and is considered to have great productive potentialities and considerable expansion possibilities due to its productive and reproductive indices, high degree of ruggedness and high quality products: cheese and meat.
- Ovis aries POU1F1 gene: cloning, characterization and polymorphism analysisPublication . Bastos, Estela; Santos, Ingrid; Parmentier, I.; Castrillo, José Luís; Cravador, A.; Guedes-Pinto, Henrique; Renaville, RobertPOU1F1 (PIT-1/GHF-1) is a transcription factor with critical role in the transcriptional regulation of multiple genes in the pituitary and also important for the survival, differentiation and proliferation of three pituitary cell types. To understand the regulation of POU1F1 gene in Ovis aries we report its cloning, sequencing and characterization. The sequenced 5787 bp included six exons and two complete introns. Ovine POU1F1 gene has a high level of conservation with its bovine, human and rat counterparts showing 98.2%, 91.2% and 86.2% of similarity at the coding level, respectively. All six exons were analyzed for polymorphism detection in 100 animals of the Portuguese indigenous ovine breed ‘Churra da Terra Quente’. One polymorphism was found at codon 58 in exon 2, in one allele of 4 animals leading to a change from cysteine to tyrosine (2% allelic frequency). In exon 3 two polymorphisms were detected: a G to A transition altering a glycine to an asparagine at codon 89 in one allele of one animal (0.5% allelic frequency) and another G to A transition at codon 105 converting an alanine into a threonine in one allele of 3 animals (1.5% allelic frequency). These polymorphisms might change the structure of the POU1F1 protein and modify gene-expression. In intron 4, an A to G transition was detected in one allele of six animals (3% allelic frequency). Exons 1, 4 and 6 showed no polymorphisms.
- Effects of genetic polymorphisms at the growth hormone gene on milk yield in “Serra da Estrela” sheepPublication . Marques, M. Rosário; Santos, Ingrid; Carolino, N.; Belo, Carmona; Renaville, Robert; Cravador, A.The five exons and the 5' and 3'-untranslated regions (5'-UTR and 3'-UTR) of the oGH gene were screened for mutations using PCR-single strand conformation polymorphism (PCR-SSCP) procedures in 523 Serra da Estrela ewes and were found to be highly polymorphic. The region extending across and between the GH2-N and GH2-Z copies was sequenced allowing the design of primers for the specific PCR amplification of each copy. These were cloned and sequenced in 20 animals representative of all SSCP patterns. The corresponding genotypes were established for each copy following nucleotide sequencing of SSCP alleles. Twenty-four polymorphic sites were found at the GH2-N (or GH1) and fourteen at the GH2-Z copies. Eight amino acid substitutions were predicted at the GH2-N and six at the GH2-Z copies. Milk yield adjusted to 150 lactation days was analysed for the genotype of each oGH gene copy taken separately or together (associated genotypes) by restricted maximum likelihood (REML) through a univariate best linear unbiased prediction (BLUP) animal model with repeated measures. Significant associations between genotypes and milk yield were observed. Within GH2-N genotypes there was a milk yield differential of 21.4+/-0.2 l/150 d between the most (N7) and the least (N5) productive ones. Within GH2-Z genotypes there was a differential of 21.6+/-0.2 l/150 d between the most (Z8) and the least (Z1) productive ones. The effect of associated GH2-N and GH2-Z genotypes revealed a differential of 39.6+/-0.3 l/150 d between the most (N1+Z7) and the least (N3+Z2) productive associated genotypes. The results show that GH2-N and GH2-Z genotypes significantly affect milk yield in Serra da Estrela ewes. Moreover, the apparent joint effect of GH2-N and GH2-Z genotype could improve milk yield in 25% as compared with the mean milk production of the analysed population.
- Polymorphisms at the five exons of gowth hormone gene in the Algarvia Goat. Possible association with milk traitsPublication . Malveiro, Elisabete; Pereira, M.; Marques, P. X.; Santos, Ingrid; Belo, Carmona; Renaville, Robert; Cravador, A.The present preliminary study attempts to establish associations between milk production traits and genetic polymorphisms at the GH gene in the Algarvia goat. The DNA of 108 goats of the indigenous Portuguese Algarvia breed was evaluated.
- Association between SSCPs at Algarvia goat GH and milk traitsPublication . Malveiro, Elisabete; Marques, P. X.; Santos, Ingrid; Belo, Carmona; Cravador, A.The DNA from one hundred eight goats belonging to the indigenous portuguese Algarvia breed was analysed. Single-strand conformation polymorphismÕs (SSCP) were identified at the five exons of the goat Growth Hormone (gGH) gene. Two conformational patterns were found in each of exons 1 and 2, four in exon 3, seven in exon 4 and five in exon 5. The establishment of an association of these SSCP patterns with milk, fat and protein production, and fat and protein content was attempted. Patterns A, F and D of exons 2, 4 and 5, respectively, are positively associated with milk, fat and protein production (p<0.05). Pattern A of exon 2 is also positively associated with fat content (p<0.05).