Wolf-Hirschhorn syndrome is a condition that affects many parts of the body. The major features of this disorder include a characteristic facial features, delayed growth and development, intellectual disability, and seizures.

Wolf-Hirschhorn syndrome is caused by a deletion of genetic material near the end of the short (p) arm of chromosome 4. This chromosomal change is sometimes written as 4p-. The size of the deletion varies among affected individuals; studies suggest that larger deletions tend to result in more severe intellectual disability and physical abnormalities than smaller deletions.

The prevalence of Wolf-Hirschhorn syndrome is estimated to be 1 in 50,000 births. However, it is likely that some affected individuals are never diagnosed.

Between 85 and 90 percent of all cases of Wolf-Hirschhorn syndrome are not inherited. They are caused by a chromosomal deletion that occurs as a random (de novo) event during the formation of reproductive cells (eggs or sperm) or during early embryonic development. More complex chromosomal rearrangements can also occur as de novo events, which may help explain the variability in the condition's signs and symptoms. De novo chromosomal changes occur in people with no history of the disorder in their family.

Published Date: May 22, 2023
Published By: National Institutes of Health