[Early genetic diagnosis in patients with HHT induced severe nosebleed].

Objective: To study the early gene diagnosis of hereditary hemorrhagic telangiectasia (HHT) induced severe nosebleed.
Method: 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.
Result: 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.
Conclusion: 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.