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Updated: May 14, 2026
08:57
Using Phylogenetic Analysis to Investigate Eukaryotic Gene Origin
Published on: August 14, 2018
Inferring evolution of gene duplicates using probabilistic models and nonparametric belief propagation
Jia Zeng1, Sridhar Hannenhalli
1School of Computer Science and Technology, Soochow University, Suzhou 215006, China. j.zeng@ieee.org
BMC Genomics
|February 2, 2013
Summary
Gene duplication drives evolutionary innovation. This study introduces a new method to simultaneously infer ancestral gene expression and the evolutionary fates (subfunctionalization, conserved function, or neofunctionalization) of gene duplicates, revealing patterns in gene family expansion.
Area of Science:
- Evolutionary biology
- Genomics
- Bioinformatics
Background:
- Gene duplication is a key driver of evolutionary innovation.
- Understanding the functional evolution of duplicate genes (paralogs) is crucial.
- Inferring the evolutionary history of gene expression and paralog fates presents significant challenges due to potential coupled evolution.
Purpose of the Study:
- To develop a novel framework for simultaneously inferring ancestral gene expression and the evolutionary fates of gene duplicates.
- To address the limitations of standard evolutionary reconstruction methods that assume independent evolution of duplicates.
- To quantitatively analyze the evolutionary fates: subfunctionalization (SF), conserved function (CF), and neofunctionalization (NF).
Main Methods:
- Proposed a probabilistic framework and algorithm for simultaneous inference.
- Developed a nonparametric belief propagation (NBP) algorithm using tissue-specific gene expression data to predict ancestral expression levels.
- Created a probabilistic model linking predicted and known expression levels to evolutionary fates (SF, NF, CF).
Main Results:
- Successfully developed and validated a novel method for inferring ancestral gene expression and paralog fates.
- Applied the method to a genome-wide set of human gene duplicates.
- The framework enables simultaneous inference, overcoming previous limitations.
Conclusions:
- Subfunctionalization (SF) appears more frequent in early stages of gene family expansion.
- Neofunctionalization (NF) is observed more frequently in later stages of gene family evolution.
- The findings provide insights into the dynamic processes shaping gene families over evolutionary time.
Related Concept Videos
02:37Gene Duplication and Divergence
The seminal work of Ohno in 1970 popularized the idea of gene duplication and divergence. DNA sequence comparison studies reveal that a large portion of the genes in bacteria, archaebacteria, and eukaryotes was generated by gene duplication and divergence, indicating its critical role in evolution.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
01:57Gene Families
Gene families consist of groups of genes proposed to have originated from a common ancestor. Typically these arise through events in which a gene or genes are mistakenly duplicated during cell division. Unlike their parent genes (which are subject to selection pressure to maintain function), these gene copies do not need to preserve their sequences and may evolve at a relatively faster rate.
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...
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The genomes of eukaryotes are punctuated by long stretches of sequence which do not code for proteins or RNAs. Although some of these regions do contain crucial regulatory sequences, the vast majority of this DNA serves no known function. Typically, these regions of the genome are the ones in which the fastest change, in evolutionary terms, is observed, because there is typically little to no selection pressure acting on these regions to preserve their sequences.
In contrast, regions which code...
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