Apert syndrome is a rare genetic condition affecting the skull and facial bones, as well as the arms and legs. This syndrome leads to craniosynostosis, which is underdevelopment of the facial bones and fusion of the fingers and toes. It occurs between one in 50,000 and one in 120,000 births.
Apert syndrome is caused by one of two possible mutations. In most cases, this mutation happens randomly. We don’t fully understand what causes this, but it doesn’t appear that it occurs as a result of something either parent does or fails to do. Most parents who have a baby with Apert syndrome have normal genes. Children with can pass the gene on to their children, however. Only one copy of the gene needs to be passed on for the new baby to have it. A parent with this syndrome has a 50-50 chance of having a baby with it. Anyone with Apert syndrome who wishes to have children should consider meeting with a geneticist to discuss the risks and make a thoughtful, informed decision.
The skull is comprised of a number of plates of bone joined together at joints called sutures. These sutures act like expansion joints, allowing the skull to get larger as your child grows and as his developing brain pushes outward. In Apert syndrome, two of these sutures fuse prematurely, preventing the child’s forehead from growing forward. When the brain cannot push the forehead forward as it grows, it pushes outward and upward in other parts of the skull where these expansion joints are functioning. This leads to a tall forehead that is too far back.
Children with this syndrome also have underdeveloped bones in the part of the face between the eyes and the mouth. The bones of the midface do not grow forward as they should. The combined effect of the slowed growth of the forehead and midface makes the eyes appear large and prominent. The eyes are normal-sized, but they are not as well protected and surrounded by bony structures as they should be, which makes them appear large.
Children also have fingers and toes fused together. The fingers and toes don’t separate while your baby is in the womb. Once your baby is born, the fingers and toes may be separated to allow your child to have more normal-appearing, useful hands and feet. Children with may also have sleep apnea due to their underdeveloped midface, reflux disease, developmental delays and a slightly higher risk of small holes between the chambers of the heart. Most often, Apert syndrome is diagnosed at birth based on the characteristic appearance of the face and the hands and feet. The suspected diagnosis may be confirmed by genetic testing.