[Analysis of a pedigree affected with hereditary coagulation factor XII deficiency due to a homozygous 252delAsn deletion of F12 gene].

To analyze the clinical phenotype and genetic basis of a consanguineous pedigree affected with hereditary coagulation factor XII (FXII) deficiency.Following extraction of genomic DNA, all exons and flanking regions of F12 gene were subjected to PCR amplification and Sanger sequencing. ClustalX-2.1-win and MutationTaster software was used to analyze the conservation and impact of the variants on protein function.DNA sequencing showed that the proband carried a homozygous g.6753-6755delACA deletion (p.252delAsn) in exon 9 of the F12 gene, for which her father, mother and brother were heterozygous carriers. The same deletion was not found in her sister.The homozygous p.252delAsn deletion probably underlies the hereditary FXII deficiency in this pedigree.