Somatic GNAQ mutation in the forme fruste of Sturge-Weber syndrome

Abstract

Objective To determine whether the GNAQ R183Q mutation is present in the forme fruste cases of Sturge-Weber syndrome (SWS) to establish a definitive molecular diagnosis. Methods We used sensitive droplet digital PCR (ddPCR) to detect and quantify the GNAQ mutation in tissues from epilepsy surgery in 4 patients with leptomeningeal angiomatosis; none had ocular or cutaneous manifestations. Results Low levels of the GNAQ mutation were detected in the brain tissue of all 4 cases - ranging from 0.42% to 7.1% frequency - but not in blood-derived DNA. Molecular evaluation confirmed the diagnosis in 1 case in which the radiologic and pathologic data were equivocal. Conclusions We detected the mutati..