ATACseq : role of trisomy 21, GATAs mutation and associated mutations in the developpment of trisomy 21

Acute megakaryoblastic leukemia of Down syndrome (DS-AMKL) is a model of clonal evolution from a preleukemic transient myeloproliferative disorder requiring both a trisomy 21 (T21) and a GATA1s mutation to a leukemia driven by additional driver mutations. We modelled this leukemic evolution through stepwise gene editing of GATA1s, SMC3+/- and MPLW515K providing 20 different trisomy or disomy 21 iPSC clones. The CD41+/CD42+ MK were sorted (10 000 to 30 000 cells) and submitted to cell lysis, transposition, and purification steps. The transposed DNA fragments were amplified by PCR 12 times using adapters from the Nextera Index Kit (Illumina). PCR purification was performed using MinElute PCR Purification Kit (Qiagen, 28004) to remove large fragments and remaining primers. Library quality was assessed using an Agilent 2100 Bioanalyzer (Agilent Technologies 5067-4626). Libraries were sequenced using NovaSeq-6000 sequencer (Illumina; 50 bp paired-end reads).