Chromosome analysis and sister chromatid exchange in encephalo-trigeminal angiodysplasia.

A female, aged 32, with facial birthmarks and suffering migraine headaches and a slight hemiparesis was examined with isotope scanning, CT and angiography. She was found to have a massive, unilateral angiodysplasia, transforming the right cerebral hemisphere into an expanding vascular sponge-like structure. There was a family history of red facial birthmarks. The patient and her father were analysed cytogenetically by estimating the frequency of chromosome aberrations and sister chromatid exchanges (SCE). The frequency of gaps and breaks was normal compared to healthy controls, but the patient showed a significantly higher level of spontaneous SCE's. The patient and her father also had a higher than normal number of SCE's after addition of mitomycin C (MMC) to the blood culture. Numerical and structural chromosome deviations markedly exceeded normal in both, possibly representing a genetic imbalance in this syndrome.