It was almost by chance that Professor John R. Østergaard of the Centre for Rare Diseases got onto the right track of the cause of a disease that affects only few children, but can be highly dangerous.
An unusual combination of symptoms in two Danish children - dilation of an artery in one place and constriction elsewhere – provided the clue when Østergaard read in a US medical journal that a gene mutation had been found in members of the same families who either suffered from dilations or constrictions.
