Guardant Health, Inc.

Other

Illumina Corporation

Andrew Kennedy

Yong Li

Stefanie Ann Ward Mortimer

Helmy A Eltoukhy

Amirali Talasaz

William J Greenleaf

Diana Abdueva

Marcin Sikora

Darya Chudova

AmirAli Talasaz

Eric Hans Vermaas

Anindita Dutta

Michelle L Alvarez

Ariel Jaimovich

Sarah E Shultzaberger

Yupeng He

Stephen Fairclough

Andrew Price

Oscar Westesson

Matthew Schultz

Rigoberto Pantoja

Jennifer Zou

Rebecca Nagy

Kimberley Banks

Matthew Feeley

Kayla Busby

Colin Brown

Richard Lanman

Christine Lee

Sequencing methods for sequencing populations of nucleic acid molecules in which sequencing reads of amplicons are grouped into families according to the nucleic acid molecule of origin by partitioning, sample indexes and information from the sequencing reads, such as start and end points. The methods described herein provide many advantages over other sequencing analysis methods, including the identification of sequencing reads deriving from the same nucleic acid in the original sample while minimizing the number of aliquots that are processed.

Sequencing methods with partitioning

The disclosure provides methods for processing nucleic acid populations containing different forms (e.g., RNA and DNA, single-stranded or double-stranded) and/or extents of modification (e.g., cytosine methylation, association with proteins). These methods accommodate multiple forms and/or modifications of nucleic acid in a sample, such that sequence information can be obtained for multiple forms. The methods also preserve the identity of multiple forms or modified states through processing and analysis, such that analysis of sequence can be combined with epigenetic analysis.

Methods and systems for analyzing nucleic acid molecules

The present disclosure provides compositions and methods related to analyzing DNA, such as cell-free DNA. In some embodiments, the cell-free DNA is from a subject having or suspected of having cancer and/or the cell-free DNA includes DNA from cancer cells. In some embodiments, the DNA is partitioned into a first subsample and a second subsample, wherein the first subsample comprises DNA with a nucleotide modification (e.g., a cytosine modification) in a greater proportion than the second subsample, and the second subsample is subjected to a procedure that affects a first nucleobase in the DNA differently from a second nucleobase in the DNA of the first subsample, and the DNA is sequenced in a manner that distinguishes the first nucleobase from the second nucleobase in the DNA of the second subsample.

Compositions and methods for analyzing DNA using partitioning and base conversion

In an aspect, the present disclosure provides a method for determining a methylation status comprises: providing a biological sample of nucleic acid molecules; partitioning at least a subset of the nucleic acid molecules in the biological sample based on the methylation status of the nucleic acid molecules into a plurality of partitioned sets; digesting at least a subset of the one or more partitioned sets in the plurality of partitioned sets with at least one methylation sensitive restriction enzyme; enriching at least a subset of the nucleic acid molecules in the plurality of partitioned sets for genomic regions of interest, wherein the at least a subset of the nucleic acid molecules comprises digested nucleic acid molecules in the one or more partitioned sets; and determining methylation status at one or more genetic loci of the nucleic acid molecules in at least one of the partitioned sets.

Methods and systems to improve the signal to noise ratio of DNA methylation partitioning assays

Sequencing nucleic acids can identify variations associated with presence, susceptibility or prognosis of disease. However, the value of such information can be compromised by errors introduced by or before the sequencing process including preparing nucleic acids for sequencing. Blunting single-stranded overhangs on nucleic acids in a sample can introduce deamination-induced sequencing errors. The disclosure provides methods of identifying and correcting for such deamination-induced sequencing errors and distinguishing them from real sequence variations.

Correcting for deamination-induced sequence errors

Disclosed herein are compositions and methods for isolating DNA, such as cell-free DNA (cfDNA). In some embodiments, the cell-free DNA is from a subject having or suspected of having cancer and/or the cell-free DNA comprises DNA produced by a tumor. In some embodiments, the DNA isolated by the method is captured using a sequence-variable target region set and an epigenetic target region set, wherein the sequence-variable target region set is captured with a greater capture yield than the epigenetic target region set. In some embodiments, captured cfDNA of the sequence-variable target region set is sequenced to a greater depth of sequencing than captured cfDNA of the epigenetic target region set.

Compositions and methods for isolating cell-free DNA

Methods of preparing double-stranded nucleic acids with single-stranded overhangs for amplification and sequencing are disclosed. Contacting a blunt-ended double-stranded nucleic acid molecules with Taq results in non-templated directed addition of a single nucleotide to the 3' ends of the nucleic acid with A added most frequently followed by G followed by C and T. G tailing is sufficiently frequent that the efficiency of ligation of nucleic acid molecules to adapters can be significantly increased by including adapters tailed with T and C. The ligation efficiency can be increased even further with blunted-ended adapters to ligate to blunt-ended nucleic acid molecules that failed to undergo tailing.

Methods of attaching adapters to sample nucleic acids

Growing community of inventors

Santa Clara, CA, United States of America

Andrew Kennedy