PATIENT X baffled his doctors. He has a rare form of anaemia normally caused by specific mutations, yet genetic tests could not explain his symptoms.
Now the doctors have cracked the problem. What they have discovered is a previously unknown mechanism that can trigger genetic illness even if the gene involved is perfectly normal.
Alpha thalassaemia occurs when one or more of the four copies of the alpha globin gene are missing. Blood counts suggested patient X had just two genes, yet genetic tests revealed he had three. For some reason, one was not working.
A team led by Douglas…
