Methylation of ASNS in normal hematopoietic cells. (A) Antileukemic activity of L-asparaginase. (B) Schematic representation of a CpG island in the mouse asparagine synthetase (Asns) gene. A CpG island is located at the boundary of the promoter and 3 initial exons. Bisulfite PCR of a 243-bp region (top panel) was performed, and the methylation status of 19 CG dinucleotides was evaluated with NGS. (C) Asns gene methylation in normal organs of fetal (E12.5), neonatal, and adult mice. Histograms of Asns methylation are indicated. (D) Schematic representation of a CpG island in the human ASNS gene. Bisulfite PCR of a 228-bp region (located at the boundary of the promoter and exon 1a) was performed, and the methylation status of 23 CG dinucleotides was evaluated. (E) ASNS methylation in normal B-cell precursors. The top panel shows a heat map of the methylation status in each CG dinucleotide. The bottom panel indicates histograms of mean percent methylation in each read.