GSX2

GSX2 is a homeobox transcription factor essential for mammalian forebrain development, particularly in specifying and patterning the basal ganglia.^[10][7] It binds specific DNA sequences, crucial for dorsal-ventral patterning of the telencephalon and specifying neural progenitors in the ventral forebrain.^[11][12]

GSX2 acts within a temporal framework, initially guiding the specification of striatal projection neurons during early lateral ganglionic eminence (LGE) neurogenesis, and later supporting olfactory bulb interneuron development.^[13] Mutations in GSX2 have been linked to basal ganglia dysgenesis in humans, resulting in severe neurological symptoms, including dystonia and intellectual impairment.^[10]

GSX2 is highly expressed in neural progenitors within the ganglionic eminences, precursors to the basal ganglia and olfactory structures. It promotes neurogenesis while inhibiting differentiation into oligodendrocytes, a type of glial cell in the central nervous system.^[7]

Mutations in GSX2 have been linked to severe neurodevelopmental disorders characterized by specific brain malformations. This includes cases of basal ganglia agenesis, leading to symptoms such as a slowly progressive decline in neurologic function, dystonia, and intellectual impairment.^[8]

A single nucleotide polymorphism and missense mutation in GSX2, rs1578004339, has been found to be a pathogenic cause of diencephalic-mesencephalic junction dysplasia syndrome, a neurodevelopmental disorder characterised by severe intellectual disability and seizures.^[8]