Avenue media on behalf of Scientific Association of Animal Production (ASPA)
Abstract
Coat colour has been a topic of interest for both breeders and geneticists. Currently most cattle
breeds are identified by their coat colour. In mammals, red/yellow and black/brown colours are determined
by the distribution of two pigments: pheomelanin and eumelanin. The relative amounts of these
pigments are primarily controlled by two loci, namely Extension (E) and Agouti (A). Extension gene encodes
a seven trans-membrane domain receptor called Melanocortin 1 Receptor (MC1R). Activation of
MC1R causes the production of eumelanin, whereas its inhibition leads to the production of pheomelanin.
In cattle, three main alleles are known for MC1R gene: i) E+ (wild type), ii) ED (dominant black),
and iii) e (recessive red). Mutations in coat colour genes have already been utilized for breed traceability
of livestock products. Sardo-Modicana is an old local breed that experienced a gradual decrease in
numbers as a result of the mechanization of agriculture. Following the recent tendency of market for
typical products, there is a renewed interest for cheese and meet produced by this breed. Traceability
protocols for this breed will be useful to guarantee the consumers and protect Sardo-Modicana breeders.
The aim of this investigation was to analyse MC1R polymorphism in Sardo-Modicana cattle breed
and evaluate if these DNA markers can be useful for product traceability in this breed. A total of 60
genomic DNA samples from Sardo-Modicana cattle collected in seven farms in the Monti Ferru area
of western Sardinia were analysed by PCR-RFLP method. DNA was amplified using specific primers
designed on the base of the bovine sequence from GenBank Acc. no. U39469. The obtained 402 bp amplicons
were separately digested with restriction endonucleases MspA1l to score allele ED and Msp1
for allele e respectively. The fragments were run on 2.5% agarose gel stained with Ethidium Bromide.
Results on Sardo-Modicana breed highlighted an almost exclusive occurrence of wild type allele except
in one animal that resulted heterozygous E+/e. A larger number of animals of the same or other breeds
farmed in Sardinia is needed to clarify if the locus polymorphism for MC1R is a valid DNA marker for
the identification of Sardo-Modicana products
