Takeaway
Heterozygous RHOBTB2 mutations account for a wider-ranging clinical phenotype, including a complex polymorphic movement disorder with paroxysmal events resembling alternating hemiplegia of childhood (AHC).
Why this matters
Heterozygous missense RHOBTB2 (known role in synaptic plasticity and cognitive function) variants have recently been reported in epileptic and developmental encephalopathies; however, these disorders have not yet been fully delineated.
The description of newly identified RHOBTB2-related disorders (RRD) may potentially aid diagnosis of AHC-like movement disorders (MDs) where patients are negative for ATPA1A3 mutations; however, further study of these rare conditions is required to facilitate greater understanding, and to potentially guide therapeutic development.