Evaluating the Accuracy of Imputation Methods in a Five-Way Admixed Population

Area of Science:

• Genomics
• Population Genetics
• Bioinformatics

Background:

• Genotype imputation enhances statistical power in genetic association analyses.
• Successful meta-analysis requires significant single nucleotide polymorphism (SNP) overlap, achievable through imputation.
• Imputation quality depends on software and reference population choice.

Purpose of the Study:

• To evaluate the accuracy and quality of genotype imputation for the five-way admixed South African Colored (SAC) population.
• To compare freely accessible imputation methods and reference panels for the SAC population.

Main Methods:

• Evaluation of imputation accuracy and quality using three freely accessible methods.
• Testing various reference populations for imputation in the SAC population.
• Utilizing the Sanger Imputation Server for imputation.

Main Results:

• The African Genome Resource was identified as the optimal reference panel for imputing missing genotypes in the SAC population.
• The Sanger Imputation Server provided accurate imputation results for the SAC population.

Conclusions:

• The African Genome Resource is recommended for genotype imputation in the South African Colored population.
• Freely accessible imputation tools, like the Sanger Imputation Server, can yield high-quality results when appropriate reference panels are used.