Five Novel Mutations in F13B Gene Resulting in Mild FXIII Deficiency

FXIII deficiency is a rare autosomal recessive disorder affecting approximately 1 out of 1–3 million inhabitants. The disease is characterized by bleeding, impaired wound repair and spontaneous abortions in females. Extracellular FXIII molecule has a tetramer structure composing of two catalytic A-subunits and two B-subunits that act as a carrier molecule. Based on genotype there are two types of FXIII deficiency: A-subunit deficiency (XIIIA) when mutations affect F13A gene and much rarely B-subunit deficiency (XIIIB) when mutations affect F13B gene. Both types result in absence of FXIII catalytical activity in plasma.