Many, but not all, lineage-specific genes can be explained by homology detection failure.
PLoS Biol
; 18(11): e3000862, 2020 11.
Article
em En
| MEDLINE
| ID: mdl-33137085
ABSTRACT
Genes for which homologs can be detected only in a limited group of evolutionarily related species, called "lineage-specific genes," are pervasive Essentially every lineage has them, and they often comprise a sizable fraction of the group's total genes. Lineage-specific genes are often interpreted as "novel" genes, representing genetic novelty born anew within that lineage. Here, we develop a simple method to test an alternative null hypothesis:
that lineage-specific genes do have homologs outside of the lineage that, even while evolving at a constant rate in a novelty-free manner, have merely become undetectable by search algorithms used to infer homology. We show that this null hypothesis is sufficient to explain the lack of detected homologs of a large number of lineage-specific genes in fungi and insects. However, we also find that a minority of lineage-specific genes in both clades are not well explained by this novelty-free model. The method provides a simple way of identifying which lineage-specific genes call for special explanations beyond homology detection failure, highlighting them as interesting candidates for further study.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Homologia de Sequência do Ácido Nucleico
/
Análise de Sequência de DNA
Tipo de estudo:
Diagnostic_studies
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article