What is Apert syndrome?
Apert syndrome is a rare genetic disorder that is identified by craniosynostosis. This is when the joints in a baby’s skull close before they should. Symptoms of Apert syndrome include head and facial deformities, as well as webbed fingers and toes. It occurs in only 1 in 65,000 births.
Causes of Apert syndrome
Apert syndrome, also known as acrocephalosyndactyly, is caused by a gene mutation. The gene affected is the fibroblast growth factor receptor-2, or FGFR2. This gene is responsible for bone growth.
The mutation interrupts proper development of the bones of the skull while the baby is in the womb. The joints, or sutures, of the skull bones close before the brain finishes growing. This results in an abnormal shape of the head as well as irregular bone formations in other parts of the body.
This gene mutation is an autosomal dominant inherited disorder. “Autosomal” means the condition is just as common in men and women. “Dominant” means an abnormal gene only needs to be passed down from one parent to be inherited. There is a 50% chance a child will have Apert syndrome if one parent has the FGFR2 mutation.
Because of craniosynostosis, there are many physical symptoms and characteristics of Apert syndrome. The severity of symptoms depends on which sutures close too soon.
Physical abnormalities may include:
Acrocephaly – tall, pointed skull
Hydrocephalus – fluid buildup in the brain
Soft spot on baby’s head that closes late
Back of skull that is flat
Hypertelorism – wide-set eyes
Exophthalmos – bulging eyes
Eyes that slant downward
Underdeveloped upper jaw
Crowding of teeth
Syndactyly – webbed, or fused, fingers or toes
These deformities can affect other parts of the body and cause further issues. These issues may include the following:
Mild to moderate cognitive and intellectual development. This is due to pressure on the brain from the abnormal shape of the skull.
Vision problems. These may occur due to an imbalance of the muscles of the eye, as the eyes may be bulging or widely spaced.
Exposure keratopathy – drying out of the cornea caused by the inability to properly close the eyelids.
Corneal scarring caused by exposure keratopathy.
Breathing problems from a flattened nose.
Ear infections and hearing loss from the malformation of the ears.
Other bones in the body, as well as the skin and organs, can also be affected. Symptoms in these areas of the body can include:
Slow bone growth in the body leading to a short stature
Abnormalities of the cervical spine
Fusion of the arm bones, wrist bones or the vertebrae of the neck
Hyperactive sweat glands
Oily skin and acne
Areas of skin with no hair
Abnormalities of the heart
An Apert syndrome diagnosis can sometimes be made before a baby is born. The doctor can perform a 2D or 3D ultrasound or an MRI during pregnancy. These scans check for abnormalities of the skull and syndactyly. The doctor can also perform genetic testing to confirm an FGFR2 gene mutation.
A diagnosis is typically made at birth or in infancy. CT scans or MRIs can find symptoms of craniosynostosis, or other bone deformities. These scans can also identify heart defects.
There are many rare, genetic disorders that present similar symptoms to Apert syndrome.
These syndromes, which also involve craniosynostosis, include:
Crouzon syndrome – A disorder much like Apert syndrome. What sets it apart is that there is no syndactyly present.
Carpenter syndrome – A disorder caused by a mutation in the RAB23 or MEGF8 genes. It has the same symptoms as Apert syndrome but is autosomal recessive. This means both parents have to pass the mutation to the child, rather than one parent.
Pfeiffer syndrome – A syndrome that causes abnormalities in the skull and middle of the face. It also causes wider thumbs and wider big toes. It occurs from a mutation in the FGFR1 and FGFR2 genes.
Saethre-Chotzen syndrome – A syndrome where the joints in the head fuse unevenly from a mutation in the TWIST 1 gene. Symptoms include wide-set eyes, strabismus (misaligned or crossed eyes), a beak-shaped nose, asymmetrical facial features and syndactyly.
Jackson-Weiss syndrome – A disorder that can cause abnormal features of the cranium and also the feet. It typically results from a mutation of the FGFR2 gene. However, this syndrome can also appear from a spontaneous mutation that is not inherited.
Antley-Bixler syndrome – A disorder caused by mutations in the POR and FGFR2 genes. Symptoms include abnormalities of the bones of the skull and face, fusion of the arm bones, very long, thin fingers and bulging eyes.
Beare-Stevenson cutis gyrata syndrome – A syndrome that involves abnormalities of the skin and skull from mutations in the FGFR2 gene.
A variety of doctors, surgeons and other medical specialists are often needed to provide a range of treatments for Apert syndrome. Treatment options depend on type and severity of symptoms.
Surgeries are scheduled during particular times of development in order to provide the best outcome.
Possible procedures include, but are not limited to:
Cranial surgeries to correct craniosynostosis, drain fluid in the brain and protect brain development
Reconstructive surgeries to correct abnormalities of the skull, jaw, chin, nose or eyes
Surgery to separate webbed fingers or toes
Tarsorrhaphy to protect the corneas
Surgery to treat heart defects
A team of medical professionals can provide other treatments that may be necessary. That team can include:
Dentists to care for crowding of teeth and general teeth health
Otolaryngologists for loss of hearing or breathing issues
Ophthalmologists to address vision and other eye problems
Cardiologists for heart problems
Speech therapists, occupational therapists and physical therapists to provide other helpful modalities
Further visits to the doctor may be needed over time to address symptoms such as sleep apnea and strabismus, which can cause amblyopia (lazy eye).
While there is not a cure, those with Apert syndrome have a full life expectancy. Surgery is important to protect the brain. Ongoing treatment helps with symptoms and possible complications as the patient grows older. Emotional support services from healthcare providers can be of assistance to the family of a loved one with Apert syndrome. And reconstructive surgeries can help those with Apert syndrome live a normal life.
Apert syndrome. Cleveland Clinic. November 2021.
Craniosynostosis. StatPearls. January 2023.
Apert syndrome. National Organization for Rare Disorders. July 2019.
Apert syndrome. Boston Children’s Hospital. Accessed June 2023.
Hydrocephalus. Cleveland Clinic. April 2022.
Apert syndrome. StatPearls. June 2023.
Exposure keratopathy. EyeWiki. American Academy of Ophthalmology. February 2023.
Crouzon syndrome. StatPearls. April 2023.
Carpenter syndrome. Cleveland Clinic. July 2022.
Pfeiffer syndrome. StatPearls. January 2023.
Saethre-Chotzen syndrome. EyeWiki. American Academy of Ophthalmology. December 2022.
Strabismus. Cleveland Clinic. January 2019.
Jackson-Weiss syndrome. National Organization for Rare Disorders. June 2020.
Antley-Bixler syndrome. National Organization for Rare Disorders. August 2019.
Beare-Stevenson cutis gyrata syndrome. National Organization for Rare Disorders. Accessed June 2023.
Apert syndrome. Medscape. August 2022.
Page published on Wednesday, June 28, 2023
Page updated on Wednesday, July 5, 2023
Medically reviewed on Wednesday, June 7, 2023