Factor XIII deficiency is a rare bleeding disorder. Researchers have identified an inherited form and a less severe form that is acquired during a person's lifetime.

Inherited factor XIII deficiency results from mutations in the F13A1 gene or, less commonly, the F13B gene. These genes provide instructions for making the two parts (subunits) of a protein called factor XIII. This protein plays a critical role in the coagulation cascade, which is a series of chemical reactions that forms blood clots in response to injury. After an injury, clots seal off blood vessels to stop bleeding and trigger blood vessel repair. Factor XIII acts at the end of the cascade to strengthen and stabilize newly formed clots, preventing further blood loss.

Inherited factor XIII deficiency affects 1 to 3 per million people worldwide. Researchers suspect that mild factor XIII deficiency, including the acquired form of the disorder, is underdiagnosed because many affected people never have a major episode of abnormal bleeding that would lead to a diagnosis.

Inherited factor XIII deficiency is considered to have an autosomal recessive pattern of inheritance, which means that it results when both copies of either the F13A1 gene or the F13B gene in each cell have mutations.

Published Date: January 01, 2019Published By: National Institutes of Health