Initial results of determination of the polymorphism of FABP4 gene and its relationship with marbling index in Wagyu crossbred cattle
This study aimed to evaluate the polymorphism of FABP4 gene in two groups of Wagyu crossbreds cattle by PCR/RFLP. A total of 112 blood samples were collected, in which 56 samples from crossbred between Wagyu×(Red Angus x Brahman crossed)-WAB and Wagyu × (Charolais x Brahman crossed)-WCB. Amplification of target gene with 565 bp and digested by NlaIII enzyme. The results showed that the polymorphic at FABP4/NlaIII were detected. There are two alleles with frequencies were G (0.853) and A (0.147) with two genotypes GG (0.705) and GA (0.295) identified. The value of He and PIC was 0.251 and 0.220, respectively. In a WAB group, the allele frequency was G (0.946) and A (0.054), the genotype frequency was GG (0.893) and GA (0.157). The value of He and PIC was 0.101 and 0.096. Similar, in the WCB group, the allele frequency was G (0.759) and A (0.241), the genotype frequency was GG (0.518) and GA (0.482). The value of He and PIC was 0.366 and 0.299. HWE testing revealed that the population was determined to be compatible with the equilibrium (P>0.05) in the total population and WAB group examined In conclusion, the polymorphic at FABP4/NlaIII was identified with two alleles and two genotypes in which the GG genotype is trended to be dominant, the value of He<Ho and low PIC in the population examined. A group of cattle with GA genotype had positive effect on marbling index at 12 months of age. Further study with increasing the sample size, relationship between genetic polymorphism with marbling index at 24 months of age and slaughter time are necessary in depth to obtain the basic data at molecular level to support the selection for improving of beef meat quality. Beside this, maintaining the GA genotype in the practical condition should be considered.
