Early genetic diagnosis in patients with HHT induced severe nosebleed
To study the early gene diagnosis of hereditary hemorrhagic telangiectasia (HHT) induced severe nosebleed. Clinical features of 23 family members in two HHT pedigrees were examined. Genomic DNA was extracted from peripheral blood samples. PCR amplification was conducted to screen ENG and ACVRL-1 genes with their specific primers. Direct sequencing was performed to detect the mutation. Mutation analysis was carried out to evaluate its significance. A heterozygous c. 263A > G mutation was identified in exon 3 of ACVRL-1 in 6 out of 11 members in NMG-1 pedigree. In GD-2 pedigree, 5 of 11 members carried c. 199C > G mutation. Mutation detection rate was 100% in subjects with nosebleed history and 25% in family members without epistaxis. Gene diagnosis characterized by high sensitivity and specificity is of great practi-cal significance and early genetic screening should be a clinical routine test for HHT induced severe nosebleed.