Which type of genes are known as paralogs?

Paralogs are genes that arise from a duplication event within the same organism's genome. As a result of this duplication, these genes can evolve and develop different functions over time while still retaining some similarities in their sequences. This is significant because it allows for the diversification of function, enabling an organism to adapt to different environmental challenges or metabolic needs.

In contrast, genes that are identical in different species are known as orthologs; they arise from a common ancestor but are separated by speciation events. Lateral gene transfer involves the acquisition of genes from another organism, commonly seen in prokaryotes, rather than from duplication. Lastly, genes with no similarities to others do not fit into the categories of paralogs, orthologs, or lateral gene transfers—these are simply unique genes without clear evolutionary connections. Thus, the characterization of paralogs as similar "paired" genes within the same organism accurately highlights their nature and evolutionary significance.