Practical Calling Approach for Exome Array-Based Genome-Wide Association Studies in Korean Population.

Area of Science:

• Genomics
• Bioinformatics
• Population Genetics

Background:

• Exome-based genotyping arrays are emerging as a cost-effective alternative to whole-exome sequencing.
• Automated clustering algorithms in exome arrays often exhibit limited accuracy for rare and low-frequency variant identification.

Purpose of the Study:

• To develop and validate a practical approach for accurate genotype calling using the Illumina Infinium HumanExome BeadChip.
• To address the genotype calling accuracy limitations of automated clustering in exome array data.

Main Methods:

• Manual genotype clustering was performed using GenomeStudio software on a dataset of 14,647 Korean samples.
• Custom cluster files were evaluated using 804 independent Korean samples on the same platform.
• Comparison and statistical summaries of genotype data were conducted.

Main Results:

• Manual genotype clustering improved the accuracy of variant identification compared to automated methods.
• The developed approach demonstrated effectiveness on the Illumina Infinium HumanExome BeadChip.
• Validation on independent samples confirmed the utility of custom cluster files.

Conclusions:

• This study provides practical guidelines for exome chip quality control, especially for Asian populations.
• The findings offer valuable insights for association studies utilizing exome chip data.
• Manual genotype clustering is a viable strategy to enhance rare variant detection in exome array studies.