Sometimes regions populated by these misplaced cells have caused a radiologic misdiagnosis of polymicrogyria. However, the presence of other abnormalities in these cobblestone lissencephaly syndromes, including ocular anomalies, congenital muscular dystrophy, ventriculomegaly, and cerebellar dysplasia, usually distinguishes these disorders from polymicrogyria. There are no anatomopathologic studies that have characterized the pattern of cortical laminar alterations in patients with GPR56 gene mutations, but it has been suggested that the imaging characteristics of BFPP, including myelination defects and cerebellar cortical dysplasia, are reminiscent of those of the so-called cobblestone malformations (muscle-eye-brain disease and Fukuyama congenital muscular dystrophy) that are also associated with N-glycosylation defects in the developing brain.Lissencephaly ("smooth brain") is the extreme form of pachygyria. In lissencephaly, few or no sulci are seen on the cortical surface, resulting in a broad, smooth appearance to the entire brain. Lissencephaly can be radiologically confused with polymicrogyria, particularly with low-resolution imaging, but the smoothness and lack of irregularity in the gray-white junction, along with markedly increased cortical thickness, distinguishes lissencephaly. GPR56 mutation also can cause a severe encelphalopathy which is associated with electro clinical features of the Lennox-Gastaut syndrome. Lennox-Gastaut syndrome can be cryptogenic or symptomatic, but the symptomatic forms have been associated with multiple etiologies and abnormal cortical development. BFPP caused by GPR56 mutations is a manifestation of a malformation of cortical development that causes Lennox-Gastaut Syndrome.Polymicrogyria is often confused  with pachygyria; therefore, it needs to be distinguished from pachygyria, a distinct brain malformation in which the surface folds are excessively broad and sparse.
In populations with a high rate of consanguinity, the offspring of a person with GPR56-related BFPP and a reproductive partner who is a carrier of GPR56-related BFPP have a 50% chance of inheriting two GPR56 disease-causing alleles and having BFPP and a 50% chance of being carriers.Other family members of a proband. Each sibling of the probands parents is at a 50% risk of being a carrier

Diagnosis
Diagnostic criteria for a BFPP patient entails a heterozygous genotype for a deletion of chromosome 16q12.1-q21 region,
including GPR56 gene. To date the only gene known to be associated with polymicrogyria is GPR56. Testing for GPR56-related bilateral frontoparietal polymicrogyria is available clinically. Mutations in GPR56 hinders Collagen III, its specific ligand, to bind in a developing brain. To date, a total of fourteen BFPP-associated mutations have been identified, including one deletion, two splicing, and eleven missense mutations. Two mutations in the GPCR proteolytic site (GPS) domain, C346S and W349S, cause a brain malformation through trapping the mutated proteins in the endoplasmic reticulum.GPR56 are a part of the B class of the GPCR family, the largest cell surface gene family in the human genome. Within this family there are different types of bio-active molecules that transduce their signal to the intracellular compartment via interaction with this type of receptor. Children often present with developmental delay, spasticity, or seizures; they are also often microcephalic. Some patients with polymicrogyria go undiagnosed until they produce children with the disorder who have more severe manifestations.