pca gwas tutorial link

pages/pca_features.md

@@ -9,6 +9,11 @@ Last update: 20250106
 
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+## PCA in genomic analysis
+
+For example of PCA correcting for population structure in GWAS see 
+<https://cloufield.github.io/GWASTutorial/05_PCA/>.
+
 ## Haplotype blocks
 
 Consider how DNA is inherited from parents: during recombination, each chromosome in the nucleus - whether autosomal (chr1-22), sex (X, Y), or mitochondrial (Mt) - receives one DNA strand from each parent.