Bilateral frontal polymicrogyria is one of the rarest subtypes of polymicrogyria. It is a symmetric and bilateral form (in both brain hemispheres) that only involves the frontal lobes without including the area located behind the Sylvius fissure or the area located behind the Rolando sulcus. Some researchers classify the condition into two different forms: bilateral frontal polymicrogyriaand the bilateral frontoparietal. Signs and symptoms included delayed motor and language milestones; spastic (stiffness) hemiparesis (weakness in one side of the body) or quadriparesis (weakness in all four limbs of the body); and mild to moderate intellectual disability. Seizures mayalsobe present. The frontoparietal form is caused by changes (mutations) in the GPR56 gene but the cause for the frontal form of polymicrogyira is still not known. Treatment is based on the signs and symptoms present in each person. The disease is Monarch Disease Ontology identifier MONDO_0016162 (bilateral frontal polymicrogyria).