GEOSEQ: a Pascal program to calculate statistical geometry parameters of aligned nucleic acid sequences

Area of Science:

• Bioinformatics
• Computational Biology
• Phylogenetics

Background:

• Statistical geometry in sequence space is a method for analyzing sequence alignments.
• It combines horizontal and vertical positional information to infer evolutionary relationships.
• Determining the correct phylogenetic topology (tree, bundle, or net) is crucial for understanding divergence.

Purpose of the Study:

• To introduce GEOSEQ, a program designed to calculate statistical geometry parameters.
• To facilitate the selection of the most appropriate phylogenetic topology for aligned sequences.
• To implement a method for assessing the statistical significance of the obtained topology through randomization.

Main Methods:

• Utilizes statistical geometry principles applied to sequence space.
• Employs the GEOSEQ program, written in Pascal.
• Input requires optimally aligned nucleic acid sequences in PHYLIP format.
• Incorporates a random sequence generator for randomization level assessment.

Main Results:

• GEOSEQ calculates parameters essential for distinguishing between phylogenetic topologies.
• The program allows for the evaluation of sequence alignment data within the framework of statistical geometry.
• Randomization tests can be performed to validate the reliability of the inferred topology.

Conclusions:

• GEOSEQ provides a computational tool for robust phylogenetic topology determination.
• The method enhances the statistical rigor of phylogenetic inference.
• This approach aids researchers in accurately reconstructing evolutionary histories from sequence data.