Vinsky, M., Islam, K., Chen, L. and Li, C. 2013. Short Communication: Association analyses of a single nucleotide polymorphism in the promoter of OLR1 with growth, feed efficiency, fat deposition, and carcass merit traits in hybrid, Angus and Charolais beef cattle. Can. J. Anim. Sci. 93: 193-197. A single nucleotide polymorphism (SNP) in the promoter region of oxidized low density lipoprotein (lectin-like) receptor 1 (OLR1) (c. -495 T>C) was identified and analyzed for associations with 10 traits related to growth, feed efficiency, body fat deposition and carcass merit traits in hybrid (n=456), Angus (n=567) and Charolais (n=423) beef cattle populations. Significant allele substitution effect (P=0.023) was found for residual feed intake (RFI) in the Angus population. The allele “C”, which had a frequency of 0.24 in the Angus population, was associated with decreased RFI. The Angus steers with the “CC” genotype had a lower RFI value (i.e., more efficient) than the Angus steers carrying the ‘TT’ genotype. The SNP was also found to have significant dominance effects on final ultrasound rib-eye area (FUREA) (P=0.0004) and carcass rib-eye area (CREA) (P=0.009) in the Angus steer population. The Angus steers with the “CT” genotype had smaller rib-eye areas of both ultrasound and carcass measures than the average of the steers with the homozygous genotypes. However, the SNP did not show significant associations with the traits examined in either the hybrid or the Charolais steer population at P<0.05. OLR1 plays a role in lipid metabolism, and analyses of transcript binding site based on the transcription element search system revealed that the “T” allele of the c.-495T>C SNP introduces a presumptive binding site for CCAAT/enhancer binding protein alpha (C/EBPa). However, further investigation is required to delineate the possible regulatory role of the SNP on growth and efficiency of energy utilization in relation to different biological types of beef cattle.