What is a analogous gene?
Analogous genes are genes that have identical or similar function but don’t share a common ancestor and are therefore unrelated as opposed to homologous genes. The main processes that result in analogous genes or structures are convergent evolution, parallel evolution, and reversals.
What does it mean if a gene is adaptive?
noun, plural: adaptive traits. A genetic trait that helps an organism to maximize its reproductive success. Supplement. For example, in hummingbirds, a long bill can be an adaptive trait since it is both heritable and adaptive.
What are orthologous genes?
Orthologs are genes in different species that evolved from a common ancestral gene by speciation, and, in general, orthologs retain the same function during the course of evolution. Identification of orthologs is a critical process for reliable prediction of gene function in newly sequenced genomes.
When do xenologous genes originate in a gene?
For xenologous genes, they originate when homologous genes are the product of horizontal gene transfer between two species and, depending on the new environment for which gene has been moved, they may have similar or distinct functions.
Is there a similar framework for classifying xenologs?
However, no comparable framework exists for xenologs: gene pairs whose history, since their divergence, includes a horizontal transfer. Further, the diversity of gene pairs that meet this broad definition calls for classification of xenologs with similar properties into subtypes.
Why is the study of paralogous genes important?
The study of paralogous genes is an important and useful tool in the study of species evolution. For xenologous genes, they originate when homologous genes are the product of horizontal gene transfer between two species and, depending on the new environment for which gene has been moved, they may have similar or distinct functions.
When did Gray and Fitch create the term xenolog?
The term ‘xenolog’, proposed by Gray and Fitch (1983) to describe horizontally transferred genes, is in use, but not widely, and there is no consensus on a precise definition.