Genetic Mutations and Environmental Exposure in Young Patients With Retinoblastoma and in Their Parents and Young Healthy Unrelated Volunteers

Intraocular Retinoblastoma Clinical Trial

Official title: Carcinogen Metabolism, DNA Repair, Parental Exposures and Retinoblastoma

Status Completed

Clinical Trial Summary

This laboratory study is looking at genetic mutations and environmental exposure in young patients with retinoblastoma and in their parents and young healthy unrelated volunteers. Gathering information about gene mutations and environmental exposure may help doctors learn more about the causes of retinoblastoma in young patients.

Clinical Trial Description

OBJECTIVES:

I. To investigate the role of genotypes for carcinogen metabolizing enzymes (CME) and DNA repair proteins(DRPs) of the father of children diagnosed with retinoblastoma (RB) and his environmental exposures prior to the child?s conception in the etiology of sporadic bilateral retinoblastoma.

II. To test if the prevalence of preconception environmental exposures and polymorphisms with known or predicted functional consequences in genes for CMEs and DRPs is different in fathers of children with sporadic bilateral RB compared with fathers of the control group.

III. To test if the prevalence of the father?s preconception environmental exposures and his polymorphisms in CMEs and DRPs differs between subsets of cases defined by the type of mutation at the RB1 gene locus.

IV. To investigate the role of genotypes for CMEs and DRPs of the mother and child and environmental exposures after the child?s conception in the etiology of sporadic unilateral RB.

V. To test if the prevalence of environmental exposures during the pregnancy and polymorphisms with known or predicted functional consequences in CMEs is different in the mothers of children with sporadic unilateral RB compared with mothers of the control group.

VI. To test if the prevalence of polymorphisms in genes for CMEs and DRPs with known or predicted functional consequences is different in the children with sporadic unilateral RB compared with controls.

VII. To test if the prevalence of gestational exposures and polymorphisms in genes for CMEs of the mother and the polymorphisms in genes for CME and DRPs in the children differs between subsets of cases defined by the type of mutation at the RB1 gene locus.

OUTLINE: This is a multicenter study.

Participants undergo a structured telephone interview questionnaire. The parental questionnaires collect basic demographic data (including age, race, education, and income), occupational history, medical radiation exposure, diet and supplement use (for the year before pregnancy for father, during pregnancy for mother), tobacco use, and alcohol use. The mothers are also asked about residential pesticides and prior assisted reproductive technology.

Controls (parents) provide saliva samples. If a patient is also enrolled on COG-ARET0332, then the patient blood and tumor samples should be submitted. Parents of patients on this protocol should also submit a blood sample. Blood samples from the affected child, and blood and/or sputum samples from the parents may be submitted. Tumor specimens should be submitted if available.

For some patients, a RB1 mutation detection assay on DNA derived from peripheral blood is performed. If the mutation is found, the parents? DNA is also screened. Blood samples undergo DNA-based sequencing analysis, single nucleotide polymorphism genotyping, quantitative Southern blot analysis, isolation of RNA and reverse transcriptase-polymerase chain reaction analysis, and loss of heterozygosity analysis. ;

Related Conditions & MeSH terms

• Extraocular Retinoblastoma
• Intraocular Retinoblastoma
• Recurrent Retinoblastoma
• Retinoblastoma

• NCT number: NCT00690469
• Study type: Observational
• Source: Children's Oncology Group
• Status: Completed
• Start date: June 2, 2008