Document Type
Article
Department/Program
Applied Science
Department
Data Science
Journal Title
BMC Bioinformatics
Pub Date
3-2019
Publisher
BMC
Volume
20
Issue
149
Abstract
Background
Gene duplications are a major source of raw material for evolution and a likely contributor to the diversity of life on earth. Duplicate genes (i.e., homeologs, in the case of a whole genome duplication) may retain their ancestral function, sub- or neofunctionalize, or be lost entirely. A primary way that duplicate genes evolve new functions is by altering their expression patterns. Comparing the expression patterns of duplicate genes gives clues as to whether any of these evolutionary processes have occurred.
Results
We develop a likelihood ratio test for the analysis of the expression ratios of duplicate genes across two conditions (e.g., tissues). We demonstrate an application of this test by comparing homeolog expression patterns of 1448 homeologous gene pairs using RNA-seq data generated from leaves and petals of an allotetraploid monkeyflower (Mimulus luteus). We assess the sensitivity of this test to different levels of homeolog expression bias and compare the method to several alternatives.
Conclusions
The likelihood ratio test derived here is a direct, transparent, and easily implemented method for detecting changes in homeolog expression bias that outperforms alternative approaches. While our method was derived with homeolog analysis in mind, this method can be used to analyze changes in the ratio of expression levels between any two genes in any two conditions.
Recommended Citation
Smith, Ronald D.; Kinser, Taliesin J.; Conradi Smith, Gregory D.; and Puzeyn, Joshua R., A Likelihood Ratio Test for Changes in Homeolog Expression Bias (2019). BMC Bioinformatics, 20(149).
https://doi.org/10.1186/s12859-019-2709-5
DOI
https://doi.org/10.1186/s12859-019-2709-5