[Early diagnosis of retinoblastoma: usefulness of searching for RB1 gene mutations].

Background: Retinoblastoma, the intraocular malignancy most common in children,occurs in both familial and sporadic (bilateral or unilateral). Hereditary predisposition is caused by a germ-line mutation while non-hereditary is due to two somatic mutations in a retinal cell. This work was carried out in order to analyse genetically, the high number of families with some affected member and to go deep into the molecular mechanisms responsible of this pathology.