MitoImpute

MitoImpute imputes missing mitochondrial single nucleotide variants (mtSNVs) to improve resolution of mitochondrial DNA (mtDNA) variant analysis for phylogenetic, haplogroup, functional, and clinical interpretation.

Key Features:

• Imputation Methodology: Uses a reference alignment of 36,960 complete human mitochondrial genomes from GenBank that undergo quality control and formatting for use with IMPUTE2.
• Pipeline Integration: Integrates the comprehensive reference alignment with the IMPUTE2 protocol, adapted for mtDNA (originally employed for chromosome X), into a cohesive imputation pipeline.
• Accuracy and Validation: Validated using the 1,000 Genomes Project and the Alzheimer's Disease Neuroimaging Initiative (ADNI), demonstrating substantial improvements in haplogroup assignment with a mean enhancement of 42.7% (Matthew's correlation coefficient = 0.64) in 1,000 Genomes samples.
• Research Impact: Enables more precise mtSNV imputation to support functional and clinical investigations and to facilitate integration of mtDNA data generated by heterogeneous methods across longitudinal studies.

Scientific Applications:

• Haplogroup and phylogenetic assignment: Enhances accuracy of haplogroup calls and phylogenetic lineage resolution from incomplete mtDNA datasets.
• Population genetics and evolutionary studies: Improves variant recovery for analyses of evolutionary relationships and population structure using mitochondrial genomes.
• Clinical association and longitudinal analyses: Supports disease association studies and the integration of historical and contemporary mtDNA data in longitudinal cohorts.

Methodology:

Constructs a reference alignment of 36,960 complete human mitochondrial genomes from GenBank, applies quality control and formatting, and performs imputation using an IMPUTE2 protocol adapted for mtDNA; validation was performed using the 1,000 Genomes Project and ADNI datasets with reported performance metrics.