Enables retinol binding activity. Involved in response to ethanol and retinol transport. Located in extracellular space. Part of protein-containing complex. Biomarker of obesity and type 2 diabetes mellitus. Human ortholog(s) of this gene implicated in type 2 diabetes mellitus. Orthologous to human RBP4 (retinol binding protein 4). [provided by Alliance of Genome Resources, Apr 2022]