hSNF5/INI1 Inactivation Is Mainly Associated with Homozygous Deletions and Mitotic Recombinations in Rhabdoid Tumors

摘要: The chromatin-remodeling hSNF5/INI1 gene has recently been shown to act as a tumor suppressor in rhabdoid tumors (RTs). In an attempt further characterize the main chromosomal mechanisms involved inactivation RTs, we report here molecular cytogenetic data obtained 12 cell lines harboring mutations and/or deletions relation genetic analysis using polymorphic markers extended both extremities of chromosome 22q. On whole, mitotic recombination occurring proximal part 22q, demonstrated five cases, and nondisjunction/duplication, highly suspected two cases (processes leading respectively partial or complete isodisomy), appear be major associated with inactivation. Such isodisomy accompanies each RTs exhibiting cytogenetically normal chromosomes 22. This results homozygosity for mutation at locus. An alternate mechanism accounting observed these is homozygous deletion consensus region. was four carrying 22q abnormality and, particular, three translocations. Only one case our series illustrates mutation/deletion classical model proposed double-hit gene.