201. Large deletions of the 5′ region of IKZF1 lead to haploinsufficiency in B‐cell precursor acute lymphoblastic leukaemia.
- Author
-
Morel, Guillaume, Deau, Marie‐Céline, Simand, Célestine, Caye‐Eude, Aurélie, Arfeuille, Chloé, Ittel, Antoine, Miguet, Laurent, Mauvieux, Laurent, Herbrecht, Raoul, Paillard, Catherine, Strullu, Marion, Cavé, Hélène, Chan, Susan, Kastner, Philippe, and Heizmann, Beate
- Subjects
REVERSE transcriptase polymerase chain reaction - Abstract
Nine of 13 (70%) MLPA-detected ex1 samples displayed exon 1 levels at half those of healthy donors, similar to samples with single I IKZF1 i copies. Both alleles were mutated (a complete deletion and a 5' deletion) in Patient 6; here, IKAROS expression was completely lost in most cells, though some cells retained intermediate IKAROS levels, suggesting clonal heterogeneity. To determine if the 5' deletions affect mRNA expression, I IKZF1 i mRNA levels from 7 ex1-only patients were compared with those of patients with different I IKZF1 i status (wildtype [WT], mono- and biallelic deletions) by reverse transcription-qPCR, using primers to amplify exons 4-5 (Fig C). One common single nucleotide polymorphism (SNP) (rs61731355; C->A at position Chr7:50,400,069 within exon 8) was detected in the gDNA and mRNA (cDNA) of 2 control patients, showing that I IKZF1 i is biallelically expressed in BCP-ALL cells (Fig D). [Extracted from the article]
- Published
- 2019
- Full Text
- View/download PDF