Colocalisation suggested a shared causal locus at <i>ADH1B</i> between alcohol intake and higher free testosterone and lower SHBG (PP4: 0.81 and 0.97 respectively).<h4>Conclusions</h4>Alcohol intake was associated with small increases in sex hormone concentrations, including bioavailable fractions, which may contribute to its effect on breast cancer risk. This evidence concerns the gene SHBG and breast cancer.