molecular marker

This wok was conducted to identify polymorphisms in the region of the exon 1 in 5'UTR of myostatin gene and their relationships with the growth traitsin Raeini cashmere goats. Myostatin gene has been identified as a factor causing a phenotype known as double-muscling in which a series of mutations render the gen inactivity; therefore, able to increase muscle growth. Blood samples were randomly taken from 150 Raeini cashmere goats. Total genomic DNA was extracted and a 701 bp fragment was amplified from the exon 1 of myostatin gene using PCR-RFLP method. The analysis of band patterns indicated three genotypes including AA, AB and BB with frequencies of 0.56, 0.33 and 0.11, respectively. The A and Balleles had a frequency of 0.72 and 0.28, respectively. The analysis of additive and dominance gene actions revealed that the effect of the myostatin gene on growth traits and body size of Raeini cashmere goats is via the dominance mechanism. The results showed that all growth traits except weaning weight were significantly associated with the identified polymorphisms, thus this gene can be used as a molecular marker in Raeini cashmere goats breeding.

The present study was attempted to produce MAS software. This software uses a combination of quantitative and molecular information for the prediction of breeding values. Some genes that control a trait have major effects comparing with others. These genes are called major genes which are located on QTLs (quantitative trait loci). Our understanding on inheritance pattern of QTL can be helpful in selection programs via marker assisted selection (MAS). This provides an opportunity to increase the genetic progress of domestic animals by MAS. The marker assisted selection performance are based on an index, consists of phenotypic and molecular markers data. The MAS software based on mixed model methods (MMM) was established with the C# programming language. This software designed based on animal models with matrix form for predicting breeding values. To identify polymorphism in promoter region of DGAT1 gene, DNA was extracted from blood samples, the PCR process performed on DNA samples. Allelic and genotypic frequencies of animals were characterized. MASS software was used for the prediction of breeding values for 80 male lambs of Afshari sheep in research-education farm of Zanjan University. To compare the results, analyses were also performed using SAS software. Comparing the predicted breeding values obtained from MAS software and SAS indicated the effect of molecular marker in selection based on the combination of molecular and phenotypic information.