A locus for bilateral occipital polymicrogyria maps to chromosome 6q16-q22.

We describe the clinical, radiographic, and genetic features of a large consanguineousMoroccan family in which bilateral occipital polymicrogyriasegregated as an autosomal recessive trait. Six affected members of the family had partial complex seizures often associated with behavioral abnormalities. On MRI, three patients had a thickened irregular cortex in the lateral occipital lobeswith small gyri. Ahigh-density genome-wide scan with 10,000 SNPs established linkage by homozygosity mapping to a 14-Mb region on chromosome 6q16–q22. Candidate genesby function ( TUBE1, GRIK2, GPRC6A, GPR6, NR2E1, MICAL1, and MARCKS) in this locus were screened for mutations.