OBJECTIVETo identify the gene mutation type of an inherited coagulation factor XIII (FXIII) deficiency pedigree.

METHODSPCR and DNA sequencing were used to identify the mutations in the 15 exons and the flank sequence of FXIII gene in the proband. The identified mutations were validated by allele specific PCR, PCR restriction fragment length polymorphism technique or DNA sequencing in the family members and 100 healthy volunteers.

RESULTSArg77Cys and Argl74stop double heterozygous mutations were discovered in the proband. The pedigree analysis showed that Arg77Cys missense mutation inherited from her father, and Arg174stop from her mother. The Arg77Cys missense mutation in exon 3 was not found in her husband and the other 100 healthy volunteers.

CONCLUSIONA novel Arg174stop nonsense mutation was discovered in human FXIII gene. A simple DNA assay based on PCR for detection of this mutation was developed. The congenital FXIII deficiency in the proband might be caused by the coinheritance of the Arg77Cys missense mutation in exon 3 and the Arg174stop nonsense mutation in exon 4.