GENETIC POLYMORPHISM AT THE Β-LACTOGLOBULIN LOCUS IN A DAIRY HERD OF ROMANIAN SPOTTED AND BROWN OF MARAMURES BREEDS
Keywords:
β-lactoglobulin, PCR-RFLP analyses, DNA genotypeAbstract
The objective of the present study was focused on possibilities to estimate the allele
and genotype frequencies of β-lactoglobulin (BLG) gene polymorphisms in dairy
cattle belonging to two different genetic groups from the Research and Development
Station for Bovine Raising Arad in order to have breeding programs that target an
increase in the frequency of the B allele in the dairy cattle population. Genotyping
was performed on 20 Romanian Spotted and 18 Brown of Maramures cattle.In order
to differentiate the favorable genotype for superior composition and higher cheese
yield, we used simple DNA extraction method from fresh blood and techniques based
on DNA analysis, which include polymerase chain reaction and restriction fragment
length polymorphisms (PCR-RFLP) methods. Employing these techniques we were
able to determine the (BLG) genotype of all individuals in a given population under
selection, regardless of sex, age or physiological stage. As a result, it is now possible
to include information on milk protein genotypes into marker assisted selection
programs and consequently improve response to selection.
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