FSTest: an efficient tool for cross-population fixation index estimation on variant call format files

Area of Science:

• Population Genetics
• Evolutionary Genetics
• Bioinformatics

Background:

• Fixation index (F) statistics are crucial for understanding genetic variation within and between populations.
• These statistics are widely used to identify genomic regions under selection pressures.

Purpose of the Study:

• Introduce FSTest 1.3 software for estimating F statistics.
• Compare FSTest 1.3 performance against VCFtools and PLINK.
• Evaluate FSTest 1.3's ability to handle low-coverage data in sliding window analyses.

Main Methods:

• Utilized chromosome 1 variant data from the 1000 Genomes Phase III (South Asian and African populations).
• Calculated F statistics for single-nucleotide polymorphisms (SNPs) using pairwise comparisons.
• Employed fixed SNP and fixed base pair sliding window approaches for analysis.

Main Results:

• FSTest 1.3 results were consistent with VCFtools and PLINK.
• Identified overestimation of F in fixed base pair window analyses with low-coverage data.
• FSTest 1.3 mitigates overestimation by averaging consecutive SNP F estimates.

Conclusions:

• FSTest 1.3 is a robust and efficient tool for F statistics estimation.
• The software effectively handles VCF files and performs rapid calculations on desktop computers.
• FSTest 1.3 offers an advantage in sliding window analyses, particularly with challenging genomic data.