NGS Data Analysis FAQ

Frequently asked questions about NGS, bioinformatics and AI-powered analysis.

Answers to common questions about next-generation sequencing data analysis, including FASTQ files, RNA-seq, DNA-seq, variant calling, ChIP-seq, ATAC-seq, bisulfite-seq, metagenomics, clinical genomics, reproducibility, reporting, and AI integration for research and industrial partners.

NGS analysis in practical terms

NGS service providers commonly deliver raw FASTQ files. Before meaningful biological interpretation, these files normally require quality control, preprocessing, alignment or quantification, statistical analysis, reporting and careful documentation.

SciBerg provides bioinformatics support for standard and custom NGS projects and can integrate AI-assisted workflows where they improve analysis organisation, literature triage, reporting, and interpretation.

1. Input FASTQ, BAM/CRAM, VCF, count tables, metadata and reference files.
2. Processing QC, trimming, mapping, quantification, calling, annotation and statistics.
3. Output Tables, figures, tracks, reports, scripts, logs and reproducible workflow notes.
4. Interpretation Biological context, clinical or translational relevance, and AI-assisted synthesis.
General NGS data analysis

General NGS data analysis

What is NGS data analysis?

NGS data analysis is the computational processing and interpretation of next-generation sequencing data. Depending on the experiment, it may include FASTQ quality control, adapter trimming, alignment or pseudoalignment, read quantification, variant calling, methylation analysis, peak calling, taxonomic profiling, statistical analysis, visualization, and biological interpretation.

What types of NGS projects can SciBerg support?

SciBerg supports common DNA-seq and RNA-seq workflows, including WGS, WES, targeted sequencing, amplicon sequencing, WTS, mRNA-seq, small RNA-seq, single-cell RNA-seq, ChIP-seq, ATAC-seq, bisulfite-seq, MeDIP/DIP-seq, and metagenomics projects.

Can SciBerg analyse raw FASTQ files from a sequencing provider?

Yes. Most sequencing providers deliver raw FASTQ files. SciBerg can process these files into project-specific outputs such as QC reports, cleaned reads, alignment files, mapping statistics, count matrices, VCF files, peak tables, methylation tables, taxonomic profiles, figures, and interpretation reports.

What information is needed before starting an NGS analysis?

At minimum, the analysis team needs the experiment type, organism and reference genome version, sample sheet, library preparation protocol, strandedness for RNA-seq, read layout, sequencing platform, group comparisons, expected outputs, and any special biological or clinical questions.

Can SciBerg help plan an NGS experiment before sequencing?

Yes. Early consultation can help define read depth, replicate number, sequencing mode, library strategy, sample metadata, controls, and downstream analysis endpoints before data are generated.

Data transfer and deliverables

Data transfer and deliverables

How can large NGS files be transferred?

Large files can usually be exchanged through secure cloud folders, institutional transfer systems, SFTP, Globus, or sequencing-provider download links. The best method depends on file size, data sensitivity, and institutional requirements.

What files are typically delivered after NGS analysis?

Typical deliverables include QC reports, processed FASTQ files when applicable, BAM or CRAM alignment files, index files, mapping statistics, count tables, VCF files, annotated variants, differential-expression tables, figures, logs, scripts, and a concise analysis report.

Will I receive the scripts used for the analysis?

Yes. SciBerg workflows can include the exact scripts, command lines, software versions, and parameters used for processing so that the analysis remains transparent and reproducible.

Can you work with data already partially analysed by another provider?

Yes. SciBerg can continue from raw FASTQ files, cleaned FASTQ files, BAM/CRAM files, count matrices, VCF files, or other intermediate results, provided the file format, reference genome, and metadata are clear.

FASTQ, QC and preprocessing

FASTQ, QC and preprocessing

What is a FASTQ file?

A FASTQ file contains sequencing reads and the corresponding base-quality information. It is often the starting point for NGS data analysis.

Why is quality control important?

Quality control helps identify adapter contamination, low-quality bases, per-base sequence bias, overrepresented sequences, low complexity, GC bias, duplicated reads, unexpected sample composition, and other issues that can influence downstream analysis.

Is adapter trimming always required?

Adapter trimming is required when adapter sequences are present in reads. It is especially important for small RNA-seq, short inserts, amplicon libraries, and low-input libraries, but the need should be evaluated from QC results.

What is the difference between single-end and paired-end reads?

Single-end sequencing reads one end of each DNA fragment. Paired-end sequencing reads both ends, improving mapping, splice-junction detection, structural-variant analysis, transcript reconstruction, and metagenomic classification.

RNA-seq

RNA-seq

What is the usual RNA-seq analysis workflow?

A typical RNA-seq workflow includes FASTQ QC, trimming if needed, alignment or pseudoalignment, gene or transcript quantification, sample-level QC, normalization, exploratory analysis, differential expression, pathway or gene-set analysis, visualization, and reporting.

What is a count matrix?

A count matrix is a table with genes or transcripts as rows and samples as columns. It contains read counts or estimated counts and is commonly used for normalization, clustering, and differential-expression analysis.

Why is strandedness important in RNA-seq?

Strandedness determines whether reads preserve information about the original RNA strand. Incorrect strandedness settings can reduce assigned reads and distort gene-expression estimates, especially for overlapping genes.

How many biological replicates are needed for RNA-seq?

The required number depends on biological variability, study design, effect size, and statistical goals. In many differential-expression studies, at least three biological replicates per group are treated as a practical minimum, but more replicates improve power and robustness.

Can SciBerg analyse small RNA-seq or miRNA-seq?

Yes. Small RNA-seq requires specialised preprocessing because inserts are short and adapter trimming is critical. The workflow may include miRNA annotation, read-length distribution, small-RNA class annotation, differential expression, and visual summaries.

DNA-seq and variant analysis

DNA-seq and variant analysis

What is the usual DNA-seq analysis workflow?

A typical DNA-seq workflow includes FASTQ QC, trimming if needed, alignment to a reference genome, duplicate marking where appropriate, mapping statistics, variant calling, variant filtering, annotation, prioritisation, and reporting.

What is the difference between WGS and WES?

Whole-genome sequencing covers the entire genome, including coding and non-coding regions. Whole-exome sequencing targets protein-coding exons and selected nearby regions, reducing cost and data volume but missing many non-coding and structural events.

What is a VCF file?

A VCF file is a Variant Call Format file. It stores detected variants, such as single nucleotide variants and small insertions or deletions, together with genomic coordinates, sample genotypes, quality metrics, and annotations.

Can SciBerg annotate and prioritise variants?

Yes. Variant annotation may include gene context, predicted consequence, known database identifiers, allele frequencies, functional predictions, clinical relevance where appropriate, inheritance models, and project-specific prioritisation.

Can you analyse targeted panels or amplicon sequencing?

Yes. Targeted and amplicon sequencing projects require workflows adapted to the panel design, primer structure, expected coverage, read layout, and variant-frequency range.

Epigenomics and chromatin

Epigenomics and chromatin

Can SciBerg analyse ChIP-seq or ATAC-seq?

Yes. ChIP-seq and ATAC-seq workflows may include QC, trimming, alignment, duplicate handling, peak calling, quality metrics, consensus peak sets, differential accessibility or binding, motif analysis, annotation, and visualization.

Can SciBerg analyse bisulfite sequencing data?

Yes. Bisulfite sequencing analysis may include specialised alignment, methylation extraction, cytosine-context analysis, methylation reports, differential methylation, and genomic-region annotation.

Metagenomics

Metagenomics

Can SciBerg analyse metagenomic sequencing data?

Yes. Metagenomic analysis may include host-read removal, taxonomic profiling, functional profiling, assembly, binning, comparative analysis, diversity analysis, and visual reporting, depending on the experimental design.

AI integration

AI integration

How can AI be integrated into bioinformatics projects?

AI can support literature triage, workflow automation, report drafting, biological interpretation, prioritisation of candidate genes or variants, internal knowledge-base creation, and interactive exploration of results. Scientific validation and transparent documentation remain essential.

Can SciBerg build custom AI-bioinformatics workflows?

Yes. SciBerg can help research and industrial partners design AI-assisted workflows that connect sequencing outputs, biological metadata, curated knowledge, publications, internal reports, and reproducible computational pipelines.

Clinical and regulated projects

Clinical and regulated projects

Can NGS data analysis be used for clinical genomics?

NGS analysis is widely used in clinical genomics, but clinical use requires careful attention to validation, documentation, quality standards, data protection, interpretation rules, and reporting requirements. The exact requirements depend on the intended use and regulatory context.

Can SciBerg support research projects with clinical samples?

Yes. SciBerg can support research projects involving clinical or translational samples, provided appropriate data-protection, consent, and project-governance requirements are in place.

Reproducibility and reporting

Reproducibility and reporting

How does SciBerg ensure reproducibility?

Reproducibility is supported by documenting software versions, reference genome versions, parameters, scripts, logs, sample metadata, and workflow decisions. Where appropriate, workflow managers and containerised software environments can also be used.

Can I get publication-ready figures?

Yes. SciBerg can prepare clear, publication-oriented figures such as QC summaries, PCA plots, heatmaps, volcano plots, genome-browser tracks, mutation summaries, methylation plots, pathway figures, and custom visualizations.

Can SciBerg help interpret results biologically?

Yes. Beyond primary processing, SciBerg can help connect results to genes, pathways, molecular mechanisms, disease context, literature, and project hypotheses.

Project logistics

Project logistics

How long does NGS analysis take?

Turnaround depends on data volume, experiment type, number of samples, requested analyses, quality issues, and reporting depth. Small standard projects may be completed relatively quickly, while complex multi-omics or clinical-genomics projects require more time.

How can I request a quote?

Send a short project description, experiment type, number of samples, organism, sequencing platform, data format, target outputs, and deadline through the SciBerg contact page or by email.