NGS using Whole Genome Amplified DNA

Reliable NGS results from limited starting materials

DNA sequence analysis and genotyping of biological samples using innovative instrumentation, such as next-generation sequencing (NGS) platforms, is often limited by the small amount of sample available. With REPLI-g technology, WGA on just single cells or non-degraded purified DNA delivers NGS results that are comparable to those obtained with unamplified gDNA.

Numerous publications have demonstrated the successful utilization of REPLI-g amplified DNA for next-generation sequencing (NGS) applications that range from exome and whole genome sequencing of tumor cells, to metagenomics research, to single cell analysis (see table).

Since the use of whole genome amplified DNA for NGS and array applications has been debated, we detected potential factors that could influence the success of using amplified DNA for these downstream applications. We determined that the quality of input material strongly influences the success of downstream NGS experiments. If working with low-quality DNA (e.g., degraded DNA) or aged tissue material, the resulting amplified DNA may not give reliable results (data not shown). However, WGA, using REPLI-g technology, on intact cells or non-degraded purified DNA, shows that NGS results are comparable to those obtained with purified gDNA. Sequence coverage and alignment comparison of the genomic loci sequence indicates minimized levels of junk DNA after WGA, whereas error rates are in a similar percentage range for both amplified and genomic DNA (see figure Comparable NGS results obtained using purified gDNA or REPLI-g Midi amplified DNA).
Comparable NGS results obtained using purified gDNA or REPLI-g Midi amplified DNA
The REPLI-g Single Cell Kit is specially designed to uniformly amplify genomic DNA (gDNA) directly from single cells (<1000 cells to as little as 1 bacterial or tumor cell) or purified gDNA, with negligible sequence bias and maximized genome coverage, making the REPLI-g Single Cell Kit an excellent tool for a wide range of NGS applications, including cancer research, metagenomics, and stem cell biology.

DNA amplified using the REPLI-g Single Cell Kit has been tested with, and is highly suited for, numerous downstream analyses, including next-generation sequencing. Since there is no requirement for a separate PCR-based amplification step, REPLI-g whole genome amplification and library preparation requires less hands-on time and results in longer read-lengths than PCR-based methods (see figure Less hands-on time and more sequence information). High-quality, comparable NGS results showing a high percentage of sequence coverage and very low error rates are achieved with both purified genomic DNA or REPLI-g Single Cell amplified DNA, including when starting from just a single bacterial cell (see figure Comparable NGS results). These findings are underscored by a comprehensive analysis of a wide range of markers covering all human autosomal chromosomes and the X chromosome, with 3 different independent experiments demonstrating that DNA is successfully amplified from all areas of the genome without a single drop-out (see figure Complete genome coverage and Unbiased DNA amplification from a single cell).
Complete genome coverage and Unbiased DNA amplification from a single cell
Unbiased amplification from a single cell is achieved with Multiple Displacement Amplification (MDA) technology and a modified form of Phi29 Polymerase (see figure Multiple Displacement Amplification (MDA) technology), along with a unique, controlled decontamination procedure to avoid amplification of contaminating DNA, ensuring highly reliable results every time (see figure Innovative UV treatment).
Unbiased DNA amplification from a single cell)
Numerous publications have demonstrated the successful utilization of REPLI-g amplified DNA for NGS applications, ranging from exome and whole genome sequencing of tumor cells, to metagenomics research, to single cell analysis.

Example citations for the successful use of REPLI-g amplified DNA in downstream NGS analysis
REPLI-g Kit Year Research topic Organism Downstream analysis Title Citation
REPLI-g Mini Kit  2012   Somatic mutations Eukaryotes/Homo sapiens Illumina HiSeq Single-cell exome sequencing and monoclonal evolution of a JAK2-negative myeloproliferative neoplasm. Hou, Y. et al. (2012) Cell 148, 873.
 2011 Congenital disease Eukaryotes/Homo sapiens Resequencing array (Affymetrix) High quality DNA sequence capture of 524 disease candidate genes. Shen, P. et al. (2011) Proc. Natl. Acad. Sci. USA 108, 6549.
 2010 Metagenomics Eukaryotes/Coryno-carpus Illumina GAII Whole genome sequencing of enriched chloroplast DNA using the Illumina GAII platform. Atherton, R.A. et al. (2010) Plant Methods 6, 22.
 2010 Methodology report Eukaryotes/Homo sapiens SOLiD 3 (Life Technologies) Semi-automated library preparation for high-throughput DNA sequencing platforms. Farias-Hesson, E., et al. (2010) J. Biomed Biotechnol 2010, 617469.
 2008 Metagenomics Prokaryotes Roche 454 Metagenomic signatures of the Peru Margin subseafloor biosphere show a genetically distinct environment. Biddle, J.F. et al. (2008) Proc. Natl. Acad. Sci. USA 105,10583
REPLI-g Midi Kit  2012 Metagenomics Prokaryotes/Clostri-diaceae Roche 454 Single-cell sequencing provides clues about the host interactions of segmented filamentous bacteria (SFB). Pamp, S.J. et al. (2012) Genome Res. 22, 1107.
 2012 Synthesis of non-methylated DNA Prokaryotes PacBio RS (Pacific Biosciences) Characterization of DNA methyltrasferase specificities using single-molecule, real-time DNA sequencing. Clark, T.A., et al. (2012) Nucleic Acids Research 40, e29.
 2012 Tropical diseases Eukaryotes/Schisto-soma Illumina GAII Whole-genome sequence of Schistosoma haematobium. Young, N.D., et al. (2012) Nat. Genet. 44, 221.
 2011 Parasitic diseases Eukaryotes/Ascaris Illumina HiSeq Ascaris suum draft genome. Jex, A.R., et al. (2011) Nature 479, 529.
REPLI-g Screening Kit  2011 Genome analysis Prokaryotes/Clostri-diaceae Roche 454 Filtering “genic” open reading frames from genomic DNA samples for advanced annotation. D’Angelo, S., et al. (2011) BMC Genomics 12 Suppl. 1, S5.
Not specified  2011 Metagenomics Eukaryotes/Plasmo-dium Illumina GAII/Illumina HiSeq Hybrid selection for sequencing pathogen genomes from clinical samples. Melnikov, A., et al (2011) Genome Biol. 12, R73.
 2011 Congenital diseases Eukaryotes/Homo sapiens Roche 454/Illumina GAII Identification of disease-causing mutations in autosomal dominant retinitis pigmentosa (adRP) using next-generation DNA sequencing. Bowne, S.J., et al. (2011) Invest. Ophthalmol. Vis. Sci. 52, 494.