Bilateral Frontoparietal Polymicrogyria (GPR56)
Bilateral frontoparietal polymicrogyria is an autosomal recessive disorder caused by pathogenic variants in the gene GPR56. This pan-ethnic disorder is characterized by severely abnormal architecture of the frontal lobes and mild involvement of the parietal and posterior parts of the cortex. Affected individuals display intellectual disability of moderate to severe degree, motor developmental delay, epilepsy, cerebellar ataxia, and problems controlling the movement of the eyes. Symptoms usually present within the first few years of life. Life expectancy it not reported, but is likely to be shortened.
For information about carrier frequency and residual risk, please see the residual risk table.