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Mutations del F508 and 4382del

What are the implications of having the combo of these 2 mutations for my niece in terms of physical effects, severity or mildness, and outcome? I have found only a little on the 4382del mutation on the internet and 2 individuals are living past there 50s.
Thank you for any and all information on the combo of these mutations.
Dear Questioner
Thank you for posting your question on our site.

There are many mutations that can cause cystic fibrosis. Some can cause mild dysfunction of the CFTR protein and therefore cause milder disease. And there are others that cause greater dysfunction of CFTR protein and generally more severe disease. It is however difficult to predict with certainty, the clinical presentation and future course of a patient’s condition based only on their genetic information. People with the same two copies of the mutated CFTR gene may experience very different symptoms. There are many factors that can influence cystic fibrosis disease. These can include factors from the patient’s environment (for example, exposure to tobacco smoke and nutrition).

There is a large database which gathers information on the clinical outcomes of patients with different mutations ( It should be noted that this can only give us trends for groups of patients, and cannot tell us exactly what is likely to happen to one particular individual. According to this database, patients who have the mutation 4382delA in combination with another CF-causing mutation such as delF508 are likely to have lung disease. The group in the CFTR database have quite a range of lung disease from mild to moderate. They may be a little less likely to be pancreatic insufficient (i.e. need to take enzyme supplements to help digest food). However, there are few patients with this mutation in the database. It is difficult to learn about trends from a small group and so the information should be interpreted with caution.

If your family have not already talked to a cystic fibrosis specialist about any concerns, we would recommend doing so. They would be able to give more specific advice after a face-to-face consultation with your niece.

Best wishes,
Lisa Kent and Damian Downey
The answer is edited by: PhD Lisa Kent