Birt-Hogg-Dubé syndrome (BHD) is a rare genetic disorder associated with lung cysts, collapsed lungs, skin lesions, and an increased risk of both benign and malignant renal tumours.  In addition to the accepted phenotypic presentation of BHD, it has been suggested that colonic polyps may also be associated with BHD syndrome. This analysis provides more precise estimates of the proportion of people carrying the gene change who show each symptom using a pooled analysis of a significant proportion of the world’s published and unpublished BHD families. By age 70 over 8 out of 10 people who carry the genetic changes responsible for BHD will have skin lesions and had a diagnosis of lung cysts or collapsed lungs. The risks of renal cancer and colonic polyps by age 70 years were lower, at a one-in-five risk. The findings did not support adding colonic polyps to the list of accepted manifestations.  As skin and lung symptoms often appear before renal cancer, there is a need to increase the awareness of BHD syndrome and its possible presentations. (By Dr Fiona Jane Bruinsma, https://jmg.bmj.com/content/early/2023/02/27/jmg-2022-109104 )