The aim of this study was to compare the allele frequency of �'-UTR NRAMP1 (Natural Resistance-Associated Macrophage Protein) microsatellite between local and specialized dairy cattle breeds reared in Sardinia, Italy. Blood samples were collected and DNA was e�tracted from ��7 Sarda, �� Italian Brown and ��� Italian Friesian cattle and analysed by means of PCR and PCR-SSCP. On the whole, three alleles were found, GT 1� , GT 14 , and GT 1� . GT 1� showed the highest frequency in all the breeds��

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... 0.874 in the Sarda, 0.��7� in the Italian Brown and 1 in the Italian Friesian. For the Sarda, both GT 14 and GT 1� showed a frequency of 0.0���, while for the Italian Brown 0.018 and 0.00��, respectively. Homozygous GT 1� /GT 1� was the unique genotype for the Italian Friesian and the most representative for the Italian Brown (0.����4) and Sarda (0.82�). The other genotypes for the Sarda were�� GT 14 /GT 14 (0.042), GT 1� /GT 14 (0.010), GT 1� /GT 1� (0.0��4) and GT 14 /GT 1� (0.0�1); as regards the Italian Brown, both GT 14 /GT 14 and GT 1� /GT 1� showed a genotypic frequency of 0.018. The observed heterozygosity was lower than the e�pected value both for the Sarda and the Italian Brown. Sarda showed a higher genetic variability than Italian Brown and Italian Friesian.