Join a team of doctors and learn about the basics of monogenic disorders and how to perform a genetic risk assessment based on family history and genetic tests. As the name suggests monogenic disorders arise due to mutations or changes in a single gene. Cystic fibrosis (CF) is the most common life‐limiting genetic disorder in those of North European descent, estimated to affect 70,000 people worldwide. CF is a monogenic disorder caused by one of over 2000 disease‐causing mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Importantly, as a recessive disorder, both copies of the gene must carry mutations for the disease to manifest.