Molecular study of the retinoblastoma in western Algerian population. Research of gene Rb mutations at the constitutional level.

Abstract

Background: Retinoblastoma is a malignant intraocular tumour which generally reaches the child with a frequency from 1/15000 to 1/20000. Antioncogene Rb changes (chromosome 13q14.2), are at the origin of this cancer. Two allele’s m u t a t i o n s of this gene are required for retinoblastoma development. The aim of this study is r e s e a r c h and i d e n t i f i c a t i o n of m u t a t i o n s able to affect the g e n e Rb a t t h e constitutional level. Methods: Study concern 61 patients. The twenty-seven exons and promoter of Rb gene were amplified by PCR, with 15 exons studied by DGGE (Denaturing Gel Gradient Electrophoresis) and 12 by SSCP (Single Strand Conformation Polymorphism). These techniques allow selecting cases for sequencing. Results: Sequencing results gave nineteen different variations bases, including seven exonic changes: five nonsens mutations located in exons 1,7,8,18 and 23 and two misense mutations in exons 19 and 20. These changes remain minority compared to the twelve intronic changes whose possible implication remains to be elucidated. Polymorphisms found in exons 2, 3,4,11 and 17 were already described in the literature. Conclusi on: Neomutations detection is important because it allows both the early treatment of children with the mutated gene that screening asymptomatic carriers at risk of transmitting the disease to their offspring. [Lotfi Louhibi, Amina Mama Boubekeur, Khadidja Mahmoudi, Rym Khadidja Abderrahmane, Fatima Zohra Nehili, Abdellah Boudjema, Meriem Aberkane, Nadhira Saidi-Mehtar. Molecular study of the retinoblastoma in western Algerian population. Research of gene Rb mutations at the constitutional level. Cancer Biology