BitEpi

BitEpi performs exhaustive searches for higher-order epistatic interactions among single nucleotide polymorphisms (SNPs/SNVs) associated with binary phenotypes such as case/control to identify multi-variant contributions to polygenic diseases.

Key Features:

• Exhaustive search up to four SNVs: Systematically tests all possible combinations of up to four bi-allelic variants (SNVs), e.g., evaluating over 230,000 4-out-of-50 combinations.
• Bitwise algorithm: Employs a novel bitwise algorithm that enables 3-SNV and 4-SNV searches to run 2.1× and 56× faster, respectively, compared to existing software.
• Entropy-based statistic and significance testing: Incorporates an entropy statistic for identifying interactive SNVs reported as 44% more accurate than traditional methods and includes p-value–based significance testing.
• Real-world dataset scale: Demonstrated on datasets comprising 4,900 samples and 87,000 SNPs to support large-scale genomic analyses.
• Visualization support: Provides visualization via EpiExplorer with integration for Cytoscape.

Scientific Applications:

• Epistasis discovery in polygenic diseases: Enables identification of higher-order SNV interactions that modulate polygenic disease risk beyond pairwise associations.
• Case/control genetic association studies: Facilitates exhaustive analysis of SNP interactions associated with binary phenotypes to inform genotype–phenotype relationships and potential therapeutic targets.

Methodology:

Systematically enumerates combinations of up to four bi-allelic variants, implements a novel bitwise algorithm, computes an entropy-based statistic for interaction detection, and applies p-value–based significance testing.