The study aimed to determine the genotypic distribution of the c.328 G>A (rs110652478) polymorphism in the bovine fatty acid-binding protein
4 (FABP4) gene and to determine its effect on slaughter weight in Aberdeen Angus and Hereford bulls imported into Turkey. A total of
randomly selected 95 bulls were used in this study. Bulls were housed for fattening in semi-open pens for approximately nine months with the
same management procedures. Genotyping of the FABP4 c.328 G>A (rs110652478) polymorphism, located in exon 3, was performed by the
PCR-RFLP method. Allele and genotype frequencies were calculated by the standard procedures and the Hardy-Weinberg equilibrium was tested
by comparing expected and observed genotype frequencies using chi-square and Fisher’s exact tests. Indices of genetic diversity were calculated
based on the allelic frequencies. The least-squares method as applied in a GLM procedure was used to test the association between FABP4 c.328
G>A and phenotypic traits including slaughter weight, hot and cold carcass weight, chilling loss, dressing percentage, and carcass pH. Results
revealed that the most frequent genotype was GG (49.18% and 52.94% for Angus and Herefords, respectively) and the minor allele frequency (A
allele) was 0.32 in the total population. The genotype distribution was in agreement with Hardy Weinberg equilibrium (P>0.05). The moderately
low levels of genetic variability observed in this study may be caused as a result of eventual inbreeding. PIC levels suggest that FABP4 c.328 G>A
can be a mildly informative genetic marker for the tested population. Association analysis indicated that the effect of the FABP4 on slaughter
weight was statistically significant (P<0.05) in the total population. However, this association was not substantiated in breed-specific analyzes.
There was no significant effect of the marker on any remaining phenotypic traits. Consequently, it is important to emphasize that analysis of
FABP4 c.328 G>A may provide valuable, but limited, information on imported beef cattle raised in Turkey conditions.