Empirical design of a variant quality control pipeline for whole genome sequencing data using replicate discordance

Robert P. Adelson, Alan E. Renton, Wentian Li, Nir Barzilai, Gil Atzmon, Alison M. Goate, Peter Davies, Yun Freudenberg-Hua

Research output: Contribution to journalArticle


The success of next-generation sequencing depends on the accuracy of variant calls. Few objective protocols exist for QC following variant calling from whole genome sequencing (WGS) data. After applying QC filtering based on Genome Analysis Tool Kit (GATK) best practices, we used genotype discordance of eight samples that were sequenced twice each to evaluate the proportion of potentially inaccurate variant calls. We designed a QC pipeline involving hard filters to improve replicate genotype concordance, which indicates improved accuracy of genotype calls. Our pipeline analyzes the efficacy of each filtering step. We initially applied this strategy to well-characterized variants from the ClinVar database, and subsequently to the full WGS dataset. The genome-wide biallelic pipeline removed 82.11% of discordant and 14.89% of concordant genotypes, and improved the concordance rate from 98.53% to 99.69%. The variant-level read depth filter most improved the genome-wide biallelic concordance rate. We also adapted this pipeline for triallelic sites, given the increasing proportion of multiallelic sites as sample sizes increase. For triallelic sites containing only SNVs, the concordance rate improved from 97.68% to 99.80%. Our QC pipeline removes many potentially false positive calls that pass in GATK, and may inform future WGS studies prior to variant effect analysis.

Original languageEnglish (US)
Article number16156
JournalScientific Reports
Issue number1
StatePublished - Dec 1 2019
Externally publishedYes


ASJC Scopus subject areas

  • General

Cite this

Adelson, R. P., Renton, A. E., Li, W., Barzilai, N., Atzmon, G., Goate, A. M., Davies, P., & Freudenberg-Hua, Y. (2019). Empirical design of a variant quality control pipeline for whole genome sequencing data using replicate discordance. Scientific Reports, 9(1), [16156]. https://doi.org/10.1038/s41598-019-52614-7