Editing Comparative genomics (section)

== Role of CNVs in evolution ==

Comparative genomics plays a crucial role in identifying [[copy number variation]]s (CNVs) and understanding their significance in evolution. CNVs, which involve [[Deletion (genetics)|deletions]] or [[Gene duplication|duplications]] of large segments of DNA, are recognized as a major source of [[genetic diversity]], influencing [[gene structure]], [[gene dosage|dosage]], and [[Regulation of gene expression|regulation]]. While single nucleotide polymorphisms (SNPs) are more common, CNVs impact larger genomic regions and can have profound effects on phenotype and diversity.<ref>{{cite journal | vauthors = Liu GE, Hou Y, Zhu B, Cardone MF, Jiang L, Cellamare A, Mitra A, Alexander LJ, Coutinho LL, Dell'Aquila ME, Gasbarre LC, Lacalandra G, Li RW, Matukumalli LK, Nonneman D, Regitano LC, Smith TP, Song J, Sonstegard TS, Van Tassell CP, Ventura M, Eichler EE, McDaneld TG, Keele JW | title = Analysis of copy number variations among diverse cattle breeds | journal = Genome Research | volume = 20 | issue = 5 | pages = 693–703 | date = May 2010 | pmid = 20212021 | pmc = 2860171 | doi = 10.1101/gr.105403.110 }}</ref> Recent studies suggest that CNVs constitute around 4.8–9.5% of the human genome and have a substantial functional and evolutionary impact. In mammals, CNVs contribute significantly to population diversity, influencing [[gene expression]] and various [[phenotypic trait]]s.<ref>{{cite journal | vauthors = Liu Y, Mu Y, Wang W, Ahmed Z, Wei X, Lei C, Ma Z | title = Analysis of genomic copy number variations through whole-genome scan in Chinese Qaidam cattle | journal = Frontiers in Veterinary Science | volume = 10 | pages = 1148070 | date = 2023 | pmid = 37065216 | doi = 10.3389/fvets.2023.1148070 | doi-access = free | pmc = 10103646 }}</ref> Comparative genomics analyses of human and chimpanzee genomes have revealed that CNVs may play a greater role in evolutionary change compared to single nucleotide changes. Research indicates that CNVs affect more nucleotides than individual base-pair changes, with about 2.7% of the genome affected by CNVs compared to 1.2% by SNPs. Moreover, while many CNVs are shared between humans and chimpanzees, a significant portion is unique to each species. Additionally, CNVs have been associated with [[genetic diseases]] in humans, highlighting their importance in human health. Despite this, many questions about CNVs remain unanswered, including their origin and contributions to evolutionary adaptation and disease. Ongoing research aims to address these questions using techniques like [[comparative genomic hybridization]], which allows for a detailed examination of CNVs and their significance. When investigators examined the raw sequence data of the human and chimpanzee.<ref>{{Cite web |title=Copy Number Variation {{!}} Learn Science at Scitable |url=http://www.nature.com/scitable/topicpage/copy-number-variation-445 |access-date=2024-05-03 |website=www.nature.com |language=en}}</ref>