ABSTRACT Single nucleotide polymorphisms are variations of a single nucleotide base pair and can be associated to phenotypic characteristics. This study aimed to determine the association of CAPN1 and CAST gene polymorphisms with the tenderness of Creole cattle meat from the Amazonas region, Peru. The texture profile (adhesiveness, cohesiveness, Warner-Bratzler shear force, elasticity, gumminess, and chewiness) of 100 animals was determined in 100 g of Longissimus dorsi et lumborum muscle. Allelic frequencies, genotypic frequencies, and Hardy-Weinberg equilibrium (HWE) of calpain (CAPN-316, CAPN-530) and calpastatin (CAST-2959) gene polymorphisms were studied. Allelic and genotypic frequencies were calculated, as well as the Hardy-Weinberg equilibrium with the Chi-square test. The texture profile of each group of samples corresponding to a polymorphism was compared with the Duncan’s test and the t-test for independent samples (p < 0.05). Genotypic frequencies were 78 % GG and 22 % CC for CAPN-316; 68 % GG, 5 % GA, and 27 % AA for CAPN-530; and 74 % AA, 18 % AG, and 8 % GG for CAST-2959. The CAPN-316, CAPN-530, and CAST-2959 polymorphisms were not in Hardy-Weinberg equilibrium. The CC genotype of CAPN-316 marker influences meat tenderness on day 21 of meat aging. In contrast, the GG genotype of CAST-2959 marker affects meat tenderness at days 14 and 21 of meat aging concerning the other genotypes. characteristics CAPN region Peru adhesiveness, adhesiveness (adhesiveness cohesiveness WarnerBratzler Warner Bratzler force elasticity gumminess chewiness 10 muscle HardyWeinberg Hardy Weinberg HWE (HWE CAPN316, CAPN316 316, 316 (CAPN-316 CAPN530 530 CAPN-530 CAST2959 2959 (CAST-2959 studied calculated Chisquare Chi square Duncans Duncan s ttest t p 0.05. 005 0.05 . 0 05 0.05) 7 2 6 GA 1 AG CAST2959. 2959. CAPN530, 530, CAST-295 CAPN-31 contrast genotypes CAPN31 31 (CAPN-31 CAPN53 53 CAPN-53 CAST295 295 (CAST-295 00 0.0 CAST-29 CAPN-3 CAPN3 3 (CAPN-3 CAPN5 CAPN-5 CAST29 29 (CAST-29 0. CAST-2 CAPN- (CAPN- CAST2 (CAST-2 CAST- (CAPN (CAST- (CAST