Li-Fraumeni syndrome is a rare disorder that greatly increases the risk of developing several types of cancer, particularly in children and young adults.

Li-Fraumeni syndrome is associated with mutations in the TP53 gene. Nearly three-quarters of families with Li-Fraumeni syndrome and about one-quarter with Li-Fraumeni-like syndrome have germline mutations in the TP53 gene. Germline mutations are typically inherited and are present in essentially every cell in the body. TP53 is a tumor suppressor gene, which means that it normally helps control the growth and division of cells. Mutations in this gene can allow cells to divide in an uncontrolled way and form tumors. Other genetic and environmental factors are also likely to affect the risk of cancer in people with TP53 mutations.

Li-Fraumeni syndrome is thought to occur in 1 in 5,000 to 1 in 20,000 people worldwide.

Li-Fraumeni syndrome is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to increase the risk of developing cancer. Most people with Li-Fraumeni syndrome inherit an altered copy of the gene from an affected parent. In 7 to 20 percent of cases, however, the altered gene is the result of a new (de novo) mutation in the gene that occurred during the formation of reproductive cells (eggs or sperm) or very early in development.

Published Date: June 01, 2020
Published By: National Institutes of Health