Welcome to LDAK-KVIK
LDAK-KVIK is a powerful and computationally efficient method for mixed-model association analysis in genome-wide association studies (GWAS). It is part of the LDAK software, which is written in C. A preprint of LDAK-KVIK is now online.
🚀 Why Use LDAK-KVIK?
- Scalability: Analyzes hundres of thousands of individuals within hours
- Statistical power: Improved detection of associated loci using an elastic net model
- Handles structure: Robust to relatedness and population stratification
- Saddlepoint approximation: Control of type 1 error when testing rare diseases or variants
- Gene-based testing: Leverage summary statistics in a gene-based association test
To download LDAK, please visit our downloads page. Example code of LDAK-KVIK can be found on the example code page. An overview of the steps involved in the LDAK-KVIK algorithm is included on the LDAK-KVIK steps page.
Stay updated with the latest developments regarding LDAK software by signing up for the LDAK mailing list.
🔧 Example code
LDAK-KVIK is run in three steps:
- Compute polygenic risk scores (PRS) using an elastic net model
- Run single-SNP association analysis using PRS as an offset
- Conduct gene-based analysis using summary statistics
Example command lines are:
./ldak6.linux --kvik-step1 kvik --bfile data --pheno phenofile --covar covfile --max-threads 4
./ldak6.linux --kvik-step2 kvik --bfile data --pheno phenofile --covar covfile --max-threads 4
./ldak6.linux --kvik-step3 kvik --bfile data --genefile genefile --max-threads 4
The main output files are:
kvik.step2.assoc
(results from single-SNP association analysis)kvik.step3.remls.all
(results from gene-based association analysis)
💻 Getting started
LDAK is available for Linux and Mac. On the Downloads page, we list several options for loading or installing the LDAK software. Explore example code and a detailed overview of the KVIK algorithm to get started.
❓ Questions or issues
If you have questions or run into issues, please raise an issue on our GitHub.