Heterozygous factor XI deficiency associated with three novel mutations

To determine the utility of single-stranded conformation polymorphism (SSCP ) analysis for screening mutations in the factor XI (fXI) gene, we investig ated three patients with heterozygous factor XI deficiency. DNA sequence an alysis confirmed three novel mutations; a CGC-->TGC (Arg308Cys) mutation in exon 9, a GCT-->GTT (Ala412Val) mutation in exon 11 and an AGC-->AGA (Ser5 76Arg) mutation in exon 15. We postulated on the structural implications of these missense mutations. Our results demonstrated that genotypic analysis is a useful tool for conclusive differentiation between heterozygous facto r XI deficiency and normal subjects.