Ring chromosome 6 syndrome is a rare chromosomal anomaly syndrome with highly variable phenotype principally characterized by prenatal/postnatal growth failure, intellectual disability, developmental delay, craniofacial dysmorphism (incl. microcephaly, microphthalmia, epicanthus, low-set and malformed ears, broad and flat nasal bridge, full lips, micrognathia), central nervous system anomalies (e.g. hydrocephalus, cortical atrophy, ventriculomegaly), short neck, and delayed bone age. Cardiac defects, limb anomalies, hip joint malformations, and seizures have also been reported.

A form of gray matter heterotopia were the mislocalized gray matter is typically located periventricularly, also sometimes called subependymal heterotopia. Periventricular means beside the ventricles. This is by far the most common location for heterotopia. Subependymal heterotopia present in a wide array of variations. There can be a small single node or a large number of nodes, can exist on either or both sides of the brain at any point along the higher ventricle margins, can be small or large, single or multiple, and can form a small node or a large wavy or curved mass.