Abstract 3118
Background
Retinoblastoma (RB) is the most common pediatric intraocular neoplasm caused by the biallelic inactivation of the RB1 tumor suppressor gene. In 40% of cases, the development of RB is mediated by a germline mutation in one of the alleles of RB1. Patients with germline mutation develop bilateral tumor with penetrance of more than 90%. However, some families demonstrate cases of RB with low penetrance (unaffected carries) and variable expressivity (carries develop either bi- or uni- RB).
It is believed that the phenotypic manifestation of hereditary retinoblastoma depends on the functional type of the germinal mutation in the RB1. The molecular mechanisms underlying the variable phenotypic manifestation of the same mutation in different family members are currently explained by the parent-of-origin effect of RB1 mutation.
Methods
Using NGS of the RB1 we have analyzed DNA from blood of 331 unrelated patients with RB (226 patients with uni- RB and 105 with bi- RB). DNA samples of available family members were also examined for the presence of an identified mutation using Sanger sequencing.
Results
We identified 11 germline mutations in the RB1 that led to the RB with low penetrance and/or variable expressivity in 12 families. Among the identified mutations:, 25.0% - are missense mutations, 58.3% - are splice mutations and 16.7% - are frame shift mutations. In 91,7% of cases, probands inherited the mutant allele from their fathers, who were either clinically healthy carriers (7 families) or had the uni-/bilateral form of RB (3 families).Table: 1170P
Mutations | Carrier (Proband, P) | Form (uni, U; bi-lateral, B; no symptoms, -) |
---|---|---|
c.1364G>C; c.1573G>A; c.1981C>T; с.607 + 1G-T (2 families); c.45_76del; с.83del | P ♂ | U - |
c.861G>C | P ♀ | U - |
c.939G>A | P ♂ Grandfather Uncle | U - - U |
c.380 + 1G-A; с.1695 + 5G-T; c.1696-2A-G | P ♂ | B U |
Conclusions
The identification of mutations in the RB1 leading to the development of RB with low penetrance and variable expressivity, is necessary for adequate treatment and competent determination of the risk of developing the disease in other family members.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
State assignment of Ministry of Science and Higher Education of the Russian Federation.
Funding
The state assignment of Ministry of Science and Higher Education of the Russian Federation.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
5579 - Quality of informed consent in clinical trials patients
Presenter: Gianluca Catania
Session: Poster Display session 3
Resources:
Abstract
5147 - Patient's rights: Where do we stand?
Presenter: Maja Kozuh
Session: Poster Display session 3
Resources:
Abstract
1279 - The oncology nurse coordinator’s role in a digestive oncology department: Impact on patient and hospital
Presenter: Fouad Awada
Session: Poster Display session 3
Resources:
Abstract
1670 - Nursing model for a breast cancer unit at the Catalan Institute of Oncology
Presenter: Ana Rodriguez-ortega
Session: Poster Display session 3
Resources:
Abstract
3936 - Role of cancer nurse in the prevention and control of acute deterioration for oncohematologic patient
Presenter: Raquel Azor Portolés
Session: Poster Display session 3
Resources:
Abstract
2789 - Standardized nursing care in the department of radiotherapy of a network of cancer centres
Presenter: José Delgado
Session: Poster Display session 3
Resources:
Abstract
4482 - Exploring anxiety, depression and quality of life of ambulatory cancer patients during chemotherapy.
Presenter: Theodoula Adamakidou
Session: Poster Display session 3
Resources:
Abstract
3075 - Implementing a Cancer Survivorship Program for Individuals with Recurrent Breast Cancer
Presenter: Darcy Burbage
Session: Poster Display session 3
Resources:
Abstract
3869 - The perceptions of parents/guardians regarding their child/adolescent’s experience of reflexology or non-specific foot massage The perceptions of parents/guardians regarding their child/adolescents experience of reflexology or non-specific foot massage
Presenter: Patricia Fox
Session: Poster Display session 3
Resources:
Abstract
4064 - Quality of life in survivors of adult haematological malignancies
Presenter: Anita Immanuel
Session: Poster Display session 3
Resources:
Abstract