Sturge-Weber syndrome is commonly associated with a somatic mutation in which gene?

Sturge-Weber syndrome is commonly associated with a somatic mutation in which gene?

• A. KRAS
• B. BRAF
• C. GNA11
• D. GNAQ

Answer: (D)

Sturge-Weber syndrome is linked to a somatic activating mutation in GNAQ, which encodes the G alpha-q subunit of heterotrimeric G proteins. This mutation occurs after fertilization in a mosaic pattern, so only some cells carry it, leading to the vascular malformations seen in the skin and leptomeninges. The common mutation (R183Q) causes constitutive GNAQ signaling, driving pathways that promote abnormal vascular development and justifying the characteristic facial port-wine stain and leptomeningeal angiomatosis. KRAS and BRAF are Ras pathway oncogenes not specifically associated with Sturge-Weber, and while GNA11 is a related gene, the classic association with this syndrome is GNAQ.

Sturge-Weber syndrome is linked to a somatic activating mutation in GNAQ, which encodes the G alpha-q subunit of heterotrimeric G proteins. This mutation occurs after fertilization in a mosaic pattern, so only some cells carry it, leading to the vascular malformations seen in the skin and leptomeninges. The common mutation (R183Q) causes constitutive GNAQ signaling, driving pathways that promote abnormal vascular development and justifying the characteristic facial port-wine stain and leptomeningeal angiomatosis. KRAS and BRAF are Ras pathway oncogenes not specifically associated with Sturge-Weber, and while GNA11 is a related gene, the classic association with this syndrome is GNAQ.