Apert syndrome is transmitted as an autosomal dominant trait (which means that only one parent needs to have the condition for a child to potentially be affected). Some cases also appear spontaneously without a family history. The condition is caused by mutations in a gene called fibroblast growth factor receptor 2.

This mutation causes some of the bony sutures of the skull close prematurely (a process called craniosynostosis) which can cause asymmetric growth and give the head a distorted shape. The face is distinctive looking and there may be full-length webbing or fusion between the 2nd, 3rd and 4th fingers, as well as the toes. In addition, as the child grows, the bones in the hands and feet become progressively fused, which reduces flexibility and function.

There are several other syndromes which have a similar appearance and include craniosynostosis (premature suture fusion):

• Carpenter syndrome (kleeblattschadel, cloverleaf skull deformity)
• Crouzon disease (craniofacial dysostosis)
• Saethre-Chotzen syndrome
• Pfeiffer syndrome

• family history of Apert syndrome
• skeletal (limb) abnormalities
• early closure of sutures between bones of the skull, noted by ridging along sutures
• large or late-closing soft spot on a baby's skull
• unusual facial appearance resulting from severe under-development of the mid-face
• prominent and/or bulging eyes
• fusion or severe webbing of several adjacent fingers and toes (severe syndactyly), often called "mitten hands"
• intellectual development may be retarded to varying degrees
• short stature
• hearing loss
• frequent ear infections

Call your health care provider if you have a family history of Apert syndrome or you notice asymmetric growth of the skull in your baby.