21,358
Genes Tested
Affymetrix HG-U133 Plus 2.0
3,358
DEGs · Entorhinal Cortex
adj.P < 0.05 · |logFC| > 1
841
DEGs · Superior Frontal Gyrus
adj.P < 0.05 · |logFC| > 1
27
Enriched Pathways · EC
Hallmark GSEA · padj < 0.05
105
Clean Samples
44 AD · 61 normal · 5 regions
01
Data Acquisition
GSE5281 downloaded from NCBI GEO using GEOquery. 161 samples across 6 brain regions on Affymetrix HG-U133 Plus 2.0.
R · GEOquery
02
Preprocessing
RMA normalization, probe-to-gene mapping via hgu133plus2.db, duplicate probe collapsing. 54,675 probes → 21,358 genes.
R · affy · biomaRt
03
Differential Expression
Region-stratified limma analysis. Design matrix with AD vs normal contrast. eBayes shrinkage. BH correction at adj.P < 0.05.
R · limma
04
Enrichment Analysis
GO ORA on significant DEGs and GSEA on full ranked gene lists using Hallmark gene sets from MSigDB.
R · clusterProfiler · fgsea
05
Python Visualization
Same DE results reproduced in Python using Seaborn and Matplotlib. PCA with scikit-learn. Clustermap of top 50 DEGs.
Python · Seaborn · sklearn
06
Interactive Dashboard
Vanilla JS dashboard using Plotly.js. Loads CSV results via fetch(). Deployed to GitHub Pages with zero backend.
JavaScript · Plotly.js