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Biology subjects

Davis, T. B.

Publications and source records attributed to Davis, T. B..

2 recordsLinked to original sources

EM-seq: Detection of DNA Methylation at Single Base Resolution from Picograms of DNA

Bisulfite sequencing is widely used to detect 5mC and 5hmC at single base resolution. However, bisulfite treatment damages DNA resulting in fragmentation, loss of DNA and biased sequencing data. To overcome this, we developed Enzymatic Methyl-seq (EM-seq), an enzymatic based approach that uses as little as 100 pg of DNA. EM-seq outperformed bisulfite converted libraries in all metrics examined including coverage, duplication, sensitivity and nucleotide composition. EM-seq libraries displayed even GC distribution, improved correlation across input amounts as well as increased representation of genomic features. These data indicate that EM-seq is more accurate and reliable than whole genome bisulfite sequencing (WGBS).

genomics

Non-destructive enzymatic deamination enables single molecule long read sequencing for the determination of 5-methylcytosine and 5-hydroxymethylcytosine at single base resolution.

The predominant methodology for DNA methylation analysis relies on the chemical deamination by sodium bisulfite of unmodified cytosine to uracil to permit the differential readout of methylated cytosines. Bisulfite treatment damages the DNA leading to fragmentation and loss of long-range methylation information. To overcome this limitation of bisulfite treated DNA we applied a new enzymatic deamination approach, termed EM-seq (Enzymatic Methyl-seq) to long-range sequencing technologies. Our methodology, named LR-EM-seq (Long Range Enzymatic Methyl-seq) preserves the integrity of DNA allowing long-range methylation profiling of 5-mC and 5-hmC over several kilobases of genomic DNA. When applied to known differentially methylated regions (DMR), LR-EM-seq achieves phasing of over 5 kb resulting in broader and better defined DMRs compared to previously reported. This result demonstrated the importance of phasing methylation for biologically relevant questions and the applicability of LR-EM-seq for long range epigenetic analysis at single molecule and single nucleotide resolution.

genomics