ortoloog

An ortolog is a gene or protein found in different species that originated from a common ancestral gene. These genes are a result of speciation, where a single gene in a common ancestor diverged into separate genes in descendant species. The key characteristic of ortologs is that they have retained similar functions despite accumulating mutations over evolutionary time. Identifying ortologs is crucial in comparative genomics and evolutionary biology. By comparing gene sequences and structures across different organisms, scientists can infer evolutionary relationships and understand the functional conservation of genes. Ortologs often play essential roles in fundamental biological processes, making them valuable targets for research, such as studying disease mechanisms or developing new therapies. For example, a gene responsible for a vital metabolic pathway in humans may have a corresponding ortolog in yeast or fruit flies, allowing researchers to study that pathway in simpler model organisms. The degree of similarity between ortologs can provide insights into the evolutionary divergence of species. Conversely, genes that arise from gene duplication within a single species are called paralogs and typically evolve new or related functions.