Splicing aberrations caused by constitutional RB1 gene mutations in retinoblastoma

Journal of biosciences

Mohammed Javed Ali²  Vidya Latha Parsam¹  Chitra Kannabiran1¹  Geeta K Vemuganti³  Santosh G Honavar² 

[1] Kallam Anji Reddy Molecular Genetics Laboratory, Hyderabad Eye Research Foundation, LV Prasad Eye Institute, Hyderabad 500 034, India$$;Ocular Oncology Service, LV Prasad Eye Institute, Hyderabad 500 034, India$$;Ophthalmic Pathology Service, LV Prasad Eye Institute, Hyderabad 500 034, India$$

关键词: Mutations;    RB1;    retinoblastoma;    RT-PCR;    splicing defects;    transcript analysis;   

DOI  :  

来源: Indian Academy of Sciences

【 摘 要 】

Analysis of RB1 mRNA from blood leukocytes of patients with retinoblastoma identified the effects of mutations involving consensus splice site, exonic substitution and whole-exon deletions identified in genomic DNA of these patients. In addition, this study identified mutations in cases in which no mutations were detectable in the genomic DNA. One proband had mutation at the canonical splice site at +5 position of IVS22, and analysis of the transcripts in this family revealed skipping of exon 22 in three members of this family. In one proband, a missense substitution of c.652T > G (g.56897T > G; Leu218Val) in exon 7 led to splicing aberrations involving deletions of exons 7 and 8, suggesting the formation of a cryptic splice site. In two probands with no detectable changes in the genomic DNA upon screening of RB1 exons and flanking intronic sequences, transcripts were found to have deletions of exon 6 in one, and exons 21 and 22 in another family. In two probands, RNA analysis confirmed genomic deletions involving one or more exons. This study reveals novel effects of RB1 mutations on splicing and suggests the utility of RNA analysis as an adjunct to mutational screening of genomic DNA in retinoblastoma.

【 授权许可】

Unknown