Genetic testing in Tunisian families with heritable retinoblastoma using a low cost approach permits accurate risk prediction in relatives and reveals incomplete penetrance in adults.
Exp Eye Res
; 124: 48-55, 2014 Jul.
Article
em En
| MEDLINE
| ID: mdl-24810223
ABSTRACT
Heritable retinoblastoma is caused by oncogenic mutations in the RB1 tumor suppressor gene. Identification of these mutations in patients is important for genetic counseling and clinical management of relatives at risk. In order to lower analytical efforts, we designed a stepwise mutation detection strategy that was adapted to the spectrum of oncogenic RB1 gene mutations. We applied this strategy on 20 unrelated patients with familial and/or de novo bilateral retinoblastoma from Tunisia. In 19 (95%) patients, we detected oncogenic mutations including base substitutions, small length mutations, and large deletions. Further analyses on the origin of the mutations showed mutational mosaicism in one unilaterally affected father of a bilateral proband and incomplete penetrance in two mothers. In a large family with several retinoblastoma patients, the mutation identified in the index patient was also detected in several non-penetrant relatives. RNA analyses showed that this mutation results in an in-frame loss of exon 9. In summary, our strategy can serve as a model for RB1 mutation identification with high analytical sensitivity. Our results point out that genetic testing is needed to reveal or exclude incomplete penetrance specifically in parents of patients with sporadic disease.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Linhagem
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Retinoblastoma
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DNA de Neoplasias
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Família
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Testes Genéticos
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Genes do Retinoblastoma
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Mutação
Tipo de estudo:
Diagnostic_studies
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Etiology_studies
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Health_economic_evaluation
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Incidence_studies
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Prognostic_studies
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Risk_factors_studies
Limite:
Adolescent
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Adult
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Aged
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Child
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Child, preschool
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Female
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Humans
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Infant
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Male
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Middle aged
País/Região como assunto:
Africa
Idioma:
En
Revista:
Exp Eye Res
Ano de publicação:
2014
Tipo de documento:
Article