Myostatin (GDF8) single nucleotide polymorphisms in Nellore cattle

ABSTRACT. The myostatin gene, also known as GDF8 (growth dif-ferentiation factor 8), is located on bovine chromosome 2 (BTA2); it has three exons and two introns. Myostatin is specifically expressed during embryonic development and in adult skeletal muscle, func-tioning as a negative regulatory protein. Several cattle breeds (Pied-montese, Belgian Blue and Blond’Aquitaine, and others) show poly-morphisms in this gene; these polymorphisms are directly related to the double muscling phenotype. We looked for polymorphisms in the Nellore cattle myostatin gene and compared them with those known for taurine breeds. Seven regions, covering the three exons of this gene, were amplified by polymerase chain reaction and se-quenced, including the untranslated region. DNA from 30 adult Nel-lore animals was collected; DNA sequencing revealed three, seven 823 ©FUNPEC-RP www.funpecrp.com.brGenetics and Molecular Research 8 (3): 822-830 (2009) Identification of polymorphisms in myostatin gene and four polymorphisms in exons 1, 2 and 3, respectively. We found previously reported polymorphisms, as well as several new ones; for instance, 37 polymorphisms were found in the untranslated re-gion segment, and in introns 1 and 2 there were one and three poly-morphisms, respectively. The high degree of allelic heterogeneity in the myostatin gene could be related to its high mutation rate; it also could be the result of a long history of artificial selection for meat production, which has probably favored such modifications and maintained them in cattle populations. These polymorphisms identified in Nellore cattle could be useful for breeding programs