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pulver: an R package for parallel ultra-rapid p-value computation for linear regression interaction terms.
Sophie Molnos1,2,3, Clemens Baumbach4,5,6, Simone Wahl4,5,6
1Research Unit of Molecular Epidemiology, Helmholtz Zentrum München, Neuherberg, Germany. Sophie.molnos@helmholtz-muenchen.de.
The new pulver R package efficiently screens for interactions between multiple "omics" data types. This tool accelerates the discovery of complex disease mechanisms by analyzing genetic variants and metabolite levels.
Area of Science:
- Genetics
- Metabolomics
- Systems Biology
Background:
- Genome-wide association studies (GWAS) investigate complex disease genetics.
- Investigating associations between genetic variants and metabolite levels is crucial for understanding disease mechanisms.
- Existing tools lack methods for large-scale analysis of interactions between diverse 'omics' data types.
Purpose of the Study:
- To develop a practical tool for large-scale screening of interaction terms between arbitrary quantitative variables.
- To enable the investigation of interplay among multiple 'omics' layers, such as DNA methylation, genetic variants, and metabolite levels.
Main Methods:
- Developed the R package 'pulver' for computing p-values in numerous linear regression models.
- Implemented an algorithm in R and C++ that utilizes the correlation coefficient for hypothesis testing, enhancing speed.
- Optimized computation by avoiding costly inversions and rearranging iteration order through 'omics' layers.
Main Results:
- The 'pulver' package significantly outperforms existing tools in speed for large-scale interaction analysis.
- Demonstrated the package's utility by applying it to real-world data from the German KORA study.
- Successfully investigated the interplay among DNA methylation, genetic variants, and metabolite levels.
Conclusions:
- 'pulver' is a fast and convenient R package for screening a vast number of linear regression models for significant interaction terms.
- The tool facilitates the analysis of interactions between any pair of quantitative variables across different 'omics' datasets.
- 'pulver' is freely available on CRAN for researchers studying complex biological systems.
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