Greig cephalopolysyndactyly syndrome (GCPS) is a congenital disorder that affects development of the limbs, head, and face. Findings might include an extra finger or toe (polydactyly), fusion of the skin between the fingers or toes (syndactyly), widely spaced eyes (ocular hypertelorism), and an abnormally large head size (macrocephaly).The features of this syndrome are highly variable, ranging from polydactyly and syndactyly of the upper and/or lower limbs to seizure, hydrocephalus , and intellectual disability. Progression of GCPS is dependent on severity. Greig cephalopolysyndactyly syndrome is caused by mutations in the GLI3 gene. This condition is inherited in an autosomal dominant pattern. Treatment is symptomatic.

The symptoms of Greig cephalopolysyndactyly syndrome (GCPS) are highly variable, ranging from mild to severe. People with this condition typically have limb anomalies, which may include one or more extra fingers or toes (polydactyly), an abnormally wide thumb or big toe (hallux), and the skin between the fingers and toes may be fused (cutaneous syndactyly). This disorder is also characterized by widely spaced eyes (ocular hypertelorism), an abnormally large head size (macrocephaly), and a high, prominent forehead. Rarely, affected individuals may have more serious medical problems including seizures, developmental delay, and intellectual disability.

GLI3 gene cause Greig cephalopolysyndactyly syndrome (GCPS). The GLI3 gene provides instructions for making a protein that controls gene expression, which is a process that regulates whether genes are turned on or off in particular cells. By interacting with certain genes at specific times during development, the GLI3 protein plays a role in the normal shaping (patterning) of many organs and tissues before birth.Different genetic changes involving the GLI3 gene can cause GCPS. In some cases, the condition results from a chromosome abnormality—such as a large deletion or rearrangement of genetic material—in the region of chromosome 7 that contains the GLI3 gene. In other cases, a mutation in the GLI3 gene itself is responsible for the disorder. Each of these genetic changes prevents one copy of the gene in each cell from producing any functional protein. It remains unclear how a reduced amount of this protein disrupts early development and causes the characteristic features of GCPS.

GLI3 gene in each cell. In some cases, an affected person inherits a gene mutation or chromosomal abnormality from one affected parent. Other cases occur in people with no history of the condition in their family. A person with GCPS syndrome has a 50% chance with each pregnancy of passing the altered gene to his or her child.

Yes. GLI3 is the only gene known to be associated with Greig cephalopolysyndactyly syndrome (GCPS). Genetic testing is available to analyze the GLI3 gene for mutations. Mutations involving GLI3 can be identified in greater than 75% of people with GCPS.

Hydrocephalus is a condition characterized by excessive accumulation of fluid in the brain. This fluid is cerebrospinal fluid (CSF) - a clear fluid that surrounds the brain and spinal cord. Excess CSF builds up when it cannot drain from the brain due to a blockage in a passage through which the fluid normally flows. This excess fluid causes an abnormal widening of spaces in the brain called ventricles; this can create harmful pressure on brain tissue.

Treatment of hydrocephalus often includes surgical insertion of a shunt system-in which a catheters (tubes) are surgically placed behind both ears. A valve (fluid pump) is placed underneath the skin behind the ear and is connected to both catheters. When extra pressure builds up around the brain, the valve opens, and excess fluid drains through the catheter. This helps lower pressure within the skull (intracranial pressure).