Polymicrogyria [242 genes]

Polymicrogyria is a malformation of the developing brain characterized by abnormal cortical lamination and an unusual folding pattern of the cerebral cortex such that all or part of the brain surface is occupied by an excessive number of small gyri. Depending on their topographic distribution, they present variable combinations of neurological symptoms of different severity, such as epilepsy, developmental delay, intellectual disability, motor dysfunction (e.g., spasticity), and pseudobulbar palsy. It is one of the most common brain malformations, representing approximately 20% of all malformations of cortical development.

Unknown overall incidence.

The service includes entities that associate polymicrogyria in isolation or as part of a complex syndromic phenotype. Thus, in a patient without a definitive diagnosis, polymicrogyria is evident by imaging testing, this panel can be a good approximation, as it includes syndromic and non-syndromic forms as well as genes involved in microdeletion – microduplication syndromes that can also associate polymicrogyria and that it could detected by exome.

The benefits derived from a genetic diagnosis in this context can range from family genetic counseling, typical of genetic studies in general, to the prevention of associated comorbidities in syndromic patients.

Service indicated when during the patient’s diagnostic process, polymicrogyria is evident by imaging test.