
Whole Genome Sequencing (WGS) is a powerful tool that can detect a broad spectrum of genetic variations, from SNP to large structural variants, across the entire genome of an individual. With decreasing sequencing costs, WGS is becoming a viable option for population-wide screening for specific disease risk, including expanded carrier testing, pharmacogenomic variants, and polygenic risk scores, for example. Additionally, WGS is also gaining interest as a complementary research tool in the context of newborn screening, a cornerstone of pediatric healthcare.
Library prep can be intimidating for labs without extensive NGS experience. The NEXTFLEX™ Rapid XP V2
NEXTFLEX Rapid XP V2 DNA-Seq Kit
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Library prep kit incorporates a streamlined protocol to simplify library prep while delivering robust results. Pooling with the NEXTFLEX UDI barcodes
NEXTFLEX UDI Barcodes (10NT, 1-24)
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enables extreme multiplexing to reduce sequencing costs. Additionally, a complete automated workflow is available for labs seeking to increase throughput and minimize human error. Using cell line-derived reference standards with known mutations, we conducted a proof-of-concept study to evaluate the suitability of the NEXTFLEX Rapid XP V2 library prep kit for detecting germline mutations. These standards offer a controlled means to assess the performance of our WGS workflow, confirming its ability to identify genetic variants in sample material. This study also highlights the potential of the NEXTFLEX Rapid XP V2 kit for comprehensive genomic analysis in research applications.
Briefly, 25 ng of Mimix™ Male Genomic DNA (HD865) reference standard was used as input for whole genome library preparation. 8 replicates were made. Libraries were made using the NEXTFLEX Rapid XP V2 DNA-seq kit
NEXTFLEX Rapid XP V2 DNA-Seq Kit for Metagenomics
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and the NEXTFLEX Unique Dual Index Barcodes
NEXTFLEX Unique Dual Index Barcodes (8NT index, 1-96)
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according to manufacturer’s instructions. The technicians that prepared libraries are experienced in molecular biology but had never used this library prep kit before. Once libraries were prepared, they were quantified using the Thermo Scientific® Qubit® assay, pooled and run on a S2 flow cell on Illumina® NovaSeq® 6000 platform at 2x150 bp read length. Analysis was performed using a custom script, using the VCF file provided for the Mimix reference standards and GRch38 build as reference.
Figure 1: Normalized coverage across varying %GC content for the 8 replicates analysed. The minimal GC bias observed indicates a high degree of coverage uniformity in the data generated.
The Mimix Male Genomic DNA reference standard contains 2,663 variants with AF<10% distributed across multiple regions, including 3’UTR, introns etc. Of those, 269 are missense variants, and they are distributed across 149 genes, all of them relevant in the context of newborn screening. Missense variants are particularly significant in genome-wide screening as they result in amino acid substitutions, directly impacting protein function. For this reason, we focus our attention to them in this test. These group of variants comprises mutations classified as benign, uncertain significance and pathogenic.
On average 626 M reads per sample were generated after sequencing. 98.3% aligned to human genome, corresponding to an average genome coverage of 56x. Coverage uniformity is important to ensure reliable and efficient identification of genetic variation across the genome. To assess the uniformity of coverage distribution in the data, we looked at the GC bias across the 8 replicates (Figure 1).
Concordance between expected genotype from Mimix and observed genotype was 100% for the 269 variants studied. The table below lists some of those variants indicating their ClinVar number, the reference and alternative allele, and the average coverage obtained across the 8 replicates for reach of the alleles.
Table 1: Detail of the 15 first variants analysed, all of them concordant with the expected genotype. A full list of the 269 variants can be provided upon request.
Gene | dbSNP ID | ClinVar | Alt(%) | Ref | Alt | Ref coverage | Alt coverage |
---|---|---|---|---|---|---|---|
HPS1 | rs58548334 | 175335 | 69.20% | A | G | 21.8 | 47.9 |
RBM20 | rs942077 | 53184 | 68.00% | G | C | 25.8 | 53.5 |
BAG3 | rs3858340 | 53943 | 48.80% | C | T | 24.6 | 46.1 |
ECHS1 | rs1049951 | 370659 | 100.00% | G | A | 0.0 | 26.9 |
ECHS1 | rs10466126 | 1245298 | 100.00% | A | G | 0.0 | 31.3 |
DCLRE1C | rs12768894 | 253714 | 61.80% | T | C | 19.1 | 20.1 |
CDH23 | rs779974496 | 1481561 | 45.50% | C | T | 26.8 | 23.0 |
CDH23 | rs1449510921 | 1319554 | 48.80% | G | A | 22.9 | 25.9 |
CDH23 | rs1227065 | 55102 | 100.00% | A | G | 0.0 | 49.8 |
CDH23 | rs1227051 | 55120 | 100.00% | G | A | 0.0 | 53.3 |
CDH23 | rs41281330 | 55122 | 45.80% | G | A | 27.1 | 21.5 |
CDH23 | rs11592462 | 55162 | 40.00% | C | G | 28.4 | 26.1 |
BMPR1A | rs11528010 | 50221 | 72.20% | C | A | 27.1 | 21.0 |
DBT | rs12021720 | 134332 | 100.00% | T | C | 0.0 | 51.1 |
ATM | rs1801516 | 133907 | 31.80% | G | A | 30.3 | 30.4 |
Figure 2: Visualization of rs1801516, located on the exon 37 of ATM (chr 11) and leading to the change p.Asp1853Asn
WGS is increasingly recognized as a pivotal tool for comprehensive screening across diverse applications. Our evaluation using Mimix reference standards demonstrates that NEXTFLEX Rapid XP V2 library preparation kit delivers uniform data coverage and enhanced variant detection accuracy, even when implemented by first-time users. These results demonstrate that laboratories can confidently adopt this robust solution regardless of their prior NGS experience, supporting reliable and consistent genomic analysis with minimal technical barriers.
NEXTFLEX Rapid XP V2 DNA-Seq Kit は、速度、データ品質、スケーラビリティを融合しています。酵素断片化によりワークフローが合理化され、独自のノーマライゼーションビーズがQCステップ全体を省略し、オプションのPCRフリー経路がライブラリーの複雑性を保ちます。サンプルを少量処理する場合でも、自動分注機上で96ウェルプレートを処理する場合でも、Illumina®およびElement AVITI™シーケンシングに対応した一貫性のある偏りのないライブラリーを作成します。
The NEXTFLEX Rapid XP v2 DNA-Seq Kit for Metagenomics combines fast, automation-ready library prep with built-in normalization and integrated downstream analysis. Designed for whole genome sequencing of microbial communities, purchase includes access to Cosmos-Hub®
for streamlined WGS metagenomics interpretation.
At Revvity Omics, we are proud to be among the first laboratories providing whole genome sequencing as a clinical service to benefit our clients and patients.