Control of performances in Asturiana de los Valles beef cattle breed involves, at present, calvings from 7,000 cows where traits as birth and weaning weight calving difficulty and double muscling scoring are registered as well as morphological and conformation traits. Breeding program is based on this performance control and on the yearly selection carried out over 120 bulls to the artificial insemination center. Genetic evaluations are performed using the mixed model methodology taking into account the variance components obtained with the same model in the same population. Efforts are managed to study the muscular hypertrophy gene because its importance has greatly increased in this population. We have proved by a classical linkage analysis a close relationship between muscular hypertrophy gene and the chromosome 2 microsatellite markers with a maximum lodscore at 3.1 cM on the telomeric side of TGLA44. Definitive location will be possible throught the identity by descent mapping strategy assuming that a set of breeds share a common ancestral mutation to exploit fine‑map gene.