Biology subjects

Easton, J.

Publications and source records attributed to Easton, J..

21 records · Page 2Linked to original sources

bioRxiv2017

Contribution Of Genetic Variation And Developmental Stage To Methylome Dynamics In Myeloid Differentiation

DNA methylation is important to establish a cells developmental identity. It also modulates cellular responses to endogenous developmental stimuli or environmental changes. We designed an in vitro myeloid differentiation model to analyze the genetic and developmental contribution to methylome dynamics using whole-genome bisulfide sequencing and transcriptome sequencing. Using a recursive partitioning approach, we identified 34,502 differentially methylated regions (DMRs) associated with genetic background and/or developmental stimuli. Specifically, 23,792 DMRs (69%) were significantly associated with inter-individual variations, of which 82% were associated with genetic polymorphisms in cis. Notably, inter-individual variations further modified 57 of 212 (26%) developmental DMRs with transcriptomic responses. Our study presents a novel analytical approach to determine the bona fide genetic contribution embedded in outlier patterns of CpG-SNPs in individual methylomes. This approach can be used to study genetic and epigenetic mechanisms underlying differential responses to developmental stimuli, environmental changes, and inter-individual differences in drug responses.

genomics↗

bioRxiv2017

Vast population genetic diversity underlies the treatment dynamics of ETV6-RUNX1 ALL

Ensemble-averaged genome profiling of diagnostic samples suggests that acute leukemias harbor few somatic genetic alterations. We used single-cell exome and error-corrected sequencing to survey the genetic diversity underlying ETV6-RUNX1 acute lymphoblastic leukemia (ALL) at high resolution. The survey uncovered a vast range of low-frequency genetic variants that were undetected in conventional bulk assays, including additional clone-specific \"driver\" RAS mutations. Single-cell exome sequencing revealed APOBEC mutagenesis to be important in disease initiation but not in progression and identified many more mutations per cell than previously found. Using this data, we created a branching model of ETV6-RUNX1 ALL development that recapitulates the genetic features of patients. Exposure of leukemic populations to chemotherapy selected for specific clones in a dose-dependent manner. Together, these data have important implications for understanding the development and treatment response of childhood leukemia, and they provide a framework for using population genetics to deeply interrogate cancer clonal evolution.\n\nOne-Sentence SummaryAPOBEC and replication-associated mutagenesis contribute to the development of ETV6-RUNX1 ALL, creating massive leukemic population genetic diversity that results in clonal differences in susceptibilities to chemotherapy.

cancer biology↗

bioRxiv2017

Genome-wide Segregation of Single Nucleotide and Structural Variants into Single Leukemia Cells

We present a new approach for determining comprehensive variant profiles of single cells using a microfluidic amplicon-based strategy. This method can be used to reconstruct the clonal architecture and mutational history of a malignancy using all classes and sizes of single nucleotide and structural variants, providing insights into the temporal changes in mutational classes and processes that led to the development of a cancer. Using this approach, we interrogated single cells from a patient with leukemia, determining that processes producing structural variation preceded single nucleotides changes in the development of that malignancy.

cancer biology↗