A novel deep intronic SERPING1 variant as a cause of hereditary angioedema due to C1-inhibitor deficiency.
Allergol Int
; 69(3): 443-449, 2020 Jul.
Article
em En
| MEDLINE
| ID: mdl-31959500
ABSTRACT
BACKGROUND:
In about 5% of patients with hereditary angioedema due to C1-inhibitor deficiency (C1-INH-HAE) no mutation in the SERPING1 gene is detected.METHODS:
C1-INH-HAE cases with no mutation in the coding region of SERPING1 after conventional genotyping were examined for defects in the intronic or untranslated regions of the gene. Using a next-generation sequencing (NGS) platform targeting the entire SERPING1, 14 unrelated C1-INH-HAE patients with no detectable mutations in the coding region of the gene were sequenced. Detected variants with a global minor allele frequency lower than the frequency of C1-INH-HAE (0.002%), were submitted to in silico analysis using ten different bioinformatics tools. Pedigree analysis and examination of their pathogenic effect on the RNA level were performed for filtered in variants.RESULTS:
In two unrelated patients, the novel mutation c.-22-155G > T was detected in intron 1 of the SERPING1 gene by the use NGS and confirmed by Sanger sequencing. All bioinformatics tools predicted that the variant causes a deleterious effect on the gene and pedigree analysis showed its co-segregation with the disease. Degradation of the mutated allele was demonstrated by the loss of heterozygosity on the cDNA level. According to the American College of Medical Genetics and Genomics 2015 guidelines the c.-22-155G > T was curated as pathogenic.CONCLUSIONS:
For the first time, a deep intronic mutation that was detected by NGS in the SERPING1 gene, was proven pathogenic for C1-INH-HAE. Therefore, advanced DNA sequencing methods should be performed in cases of C1-INH-HAE where standard approaches fail to uncover the genetic alteration.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Íntrons
/
Predisposição Genética para Doença
/
Proteína Inibidora do Complemento C1
/
Angioedemas Hereditários
/
Mutação
Tipo de estudo:
Diagnostic_studies
/
Prognostic_studies
Limite:
Humans
Idioma:
En
Revista:
Allergol Int
Assunto da revista:
ALERGIA E IMUNOLOGIA
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
Grécia