Cattle intended for meat production have improved over time thanks to rigorous genetic selection implemented to preserve and transmit characteristics such as marbling and tenderness of beef from generation to generation. Variation in beef tenderness between breeds has been reported by Marshall (1999) and Burrow et al. (2001); It is one of the most valued attributes (Miller, 1992; Boleman et al., 1997). Many genetic characteristics linked to meat quality involve a specific number of genes, some genes in particular express a significant percentage of the compositional variability and quality of meat (Burrow et al., 2001). quality of beef, one of the candidate genes is the PPARGC1 gene which encodes peroxisome proliferator-activated receptor gamma coactivator 1 alpha, which is a cofactor that is involved in the transcription of some genes, including MEF2 (Muscle Enhancer Factor). adipose tissue cells are linked to marbling, because it coactivates PPAR€, PPAR and thyroid hormones (Puigserver, et al., 1998) allowing the fixation of intramuscular fat. Another gene of great importance in meat improvement is the capn1 gene (large subunit of μ-calpain) which has been associated with tenderness (Smith et al., 2000; Page et al., 2002, 2004); In the case of the ppargc1a gene, a high frequency of heterozygotes (CT) was observed. The C allele has been considered the most favorable to meat tenderness (White et al., 2005). Currently, SNPs (single nucleotide polymorphisms) have been found in the proteins Leptin,...... middle of paper.... ..nes of G and A in both populations of Colombian Creole cattle (B. Taurus and B. Indicus) which is directly related to the production of lean meat and the content of good marble. Works Cited http:// http:// acteon.webs.upv.es/CONGRESOS/AIDA%202003/checa.pdfhttp://biblioteca.ucm.es/tesis/vet/ucm-t26294.pdfhttp://www. redalyc.org/pdf/495/49520788041. pdfhttp://rccp.udea.edu.co/index.php/ojs/article/view/777/840http://www.uco.es/conbiand/aica/templatemo_110_lin_photo/articulos/2012/Trabajo072_AICA2012.pdfhttp:// biblioteca.ucm.es/tesis/vet/ucm-t26294.pdfhttp://itzamna.bnct.ipn.mx/dspace/bitstream/123456789/8886/1/ANAGENES.pdfhttp://www.colvema.org/pdf/ 6473geneticaii.pdf