Phenotypic Spectrum of GNA11R183C Mosaicism.

ABSTRACT Background Methods Results Conclusion Many vascular anomalies harbor postzygotic somatic variants in GNAQ and GNA11; however, the phenotype of specific G‐protein variants has not been well described. We report the clinical characteristics of 17 patients with a GNA11 R183C variant.This case series is derived from a multinational cohort of vascular anomaly patients whose pathogenic mutations were identified using high‐depth next generation sequencing. Data include vascular anomaly features, imaging reports, and extracutaneous manifestations of the GNA11 R183C variant.We identified 17 subjects (median age 18 years [range 6–67]) with somatic GNA11 R183C variant. All patients had vascular lesions of the skin that presented as pink‐to‐red in children and deeper red in adults. Most lesions were large, poorly demarcated, and reticulated patches that were often bilaterally distributed. Nevus anemicus was observed in 53% (N = 9) and dermal melanocytosis in 13.3% (N = 2) of individuals. 82% (N = 14) of patients had limb growth discrepancies, and 1 patient had marked thoracic hypoplasia. 47% (N = 8) of patients had facial involvement, and 41% (N = 7) had forehead involvement. One patient experienced seizures due to right hemispheric leptomeningeal angiomatosis consistent with Sturge–Weber syndrome. Other findings included glaucoma (29%, N = 5) and psychomotor delay (29%, N = 5).These findings contribute to our understanding of the clinical spectrum of GNA11 R183C capillary malformations (CMs); patients characteristically present with extensive, bilateral, poorly demarcated, pink‐to‐red CMs associated with nevus anemicus. Glaucoma and growth discrepancies (overgrowth or undergrowth) are common. Leptomeningeal angiomatosis and developmental delay can occur, appearing potentially less prevalent and severe than GNAQ‐associated disease. [ABSTRACT FROM AUTHOR]