Notes from the bench

Bioinformatics, with the receipts.

Specific troubleshooting, tool comparisons, and workflow notes from real client projects. No "intro to RNA-seq" — only the parts that actually trip people up.

2026-06-19

GSEA vs over-representation analysis in RNA-seq: why your DEG list misses pathways GSEA still finds

Over-representation analysis throws away every gene below your cutoff. GSEA ranks all of them. When that difference decides whether you see the biology, and the two settings that make or break the result.

#rna-seq#gsea#enrichment-analysis#pathway-analysis#fgsea
2026-05-29

The DESeq2 log fold change threshold: when |log2FC| > 1 is the wrong ruler

The 2-fold cutoff is a cell-line habit that quietly discards real signal in clinical RNA-seq. When to lower it, why lfcShrink matters, and how to test against a threshold instead of filtering after the fact.

#rna-seq#deseq2#differential-expression#lfcshrink#statistics
2026-05-22

RNA-seq from FASTQ to DE: what a reproducible pipeline actually looks like in 2026

End-to-end RNA-seq workflow: QC, alignment, quantification, DESeq2, pathway analysis, reporting. The five stages, the real tool choices, and what production looks like in Snakemake.

#rna-seq#snakemake#deseq2#workflow#bioinformatics
2026-05-14

PCA before DESeq2: the 30-second sanity check that catches what DE misses

Running PCA before differential expression takes 30 seconds and catches batch effects, mislabeled samples, and outliers that silently destroy DESeq2 results. How to read it.

#rna-seq#deseq2#qc#pca#batch-effects
2026-05-12

Tumor-only WGS variant calling without matched normal: what actually works in 2026

Why tumor-only somatic calling is harder than the docs admit, and a layered filter strategy that keeps false-positive rate manageable: PoN, gnomAD AF, and signature-based germline cleanup.

#wgs#somatic#mutect2#tumor-only#ffpe