Sequence homology

<p>Sequence homology is the <a href="/facts/Homology_(biology)/muctKlyT">biological homology</a> between <a href="/facts/DNA_sequence/hsPsNCQW">DNA</a>, <a href="/facts/RNA_sequence/qAf4kTee">RNA</a>, or <a href="/facts/Protein_primary_structure/QNBoERdu">protein sequences</a>, defined in terms of shared ancestry in the <a href="/facts/Evolutionary_history_of_life/Ss6eB0EX">evolutionary history of life</a>. Two segments of DNA can have shared ancestry because of three phenomena: either a <a href="/facts/Speciation/pmRTQbTK">speciation</a> event (orthologs), or a <a href="/facts/Gene_duplication/CcfJYsDF">duplication event</a> (paralogs), or else a <a href="/facts/Horizontal_gene_transfer/FPyUIsf2">horizontal (or lateral) gene transfer</a> event (xenologs).
</p><p>Homology among DNA, RNA, or proteins is typically inferred from their <a href="/facts/Nucleotide/pQKEwlJI">nucleotide</a> or <a href="/facts/Amino_acid/WDxYwBny">amino acid</a> sequence similarity. Significant similarity is strong evidence that two sequences are related by evolutionary changes from a common ancestral sequence. <a href="/facts/Sequence_alignment/p8GQfF7b">Alignments</a> of multiple sequences are used to indicate which regions of each sequence are homologous.
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Sequence homology open-in-new

Sequence homology