Among case-control studies, Abbas and colleagues [26] observed a significant association with adulthood overweight/obesity status and increased likelihood of breast cancer (overweight: OR 3.06, 95%CI 1.36,6.87; obesity: OR 4.09, 95%CI 1.91,8.75) among 200 women with BRCA1/2 pathogenic germline gene variants. This evidence concerns the gene BRCA1 and obesity due to melanocortin 4 receptor deficiency.