SHBG and obesity due to melanocortin 4 receptor deficiency: While obesity and female sex hormones are known risk factors, the role of sex hormone-binding globulin (SHBG) and testosterone in gallstone-related risk, and whether they mediate the association between obesity and gallbladder disease, remain unclear.<h4>Methods</h4>We included 176,909 men and 160,147 women from the UK Biobank.