https://en.wikipedia.org/wiki/Human_accelerated_region_1 Jump to content [ ] Main menu Main menu move to sidebar hide Navigation * Main page * Contents * Current events * Random article * About Wikipedia * Contact us Contribute * Help * Learn to edit * Community portal * Recent changes * Upload file * Special pages [enwiki] Wikipedia The Free Encyclopedia Search [ ] Search [ ] Appearance * Donate * Create account * Log in [ ] Personal tools * Donate * Create account * Log in Contents move to sidebar hide * (Top) * 1 HAR1A * 2 HAR1B * 3 See also * 4 References Toggle References subsection + 4.1 Further reading * 5 External links [ ] Toggle the table of contents Human accelerated region 1 [ ] 3 languages * Nederlands * Russkii * Ukrayins'ka Edit links * Article * Talk [ ] English * Read * Edit * View history [ ] Tools Tools move to sidebar hide Actions * Read * Edit * View history General * What links here * Related changes * Upload file * Permanent link * Page information * Cite this page * Get shortened URL Print/export * Download as PDF * Printable version In other projects * Wikidata item Appearance move to sidebar hide From Wikipedia, the free encyclopedia Segment of chromosome 20 in humans RNA family Highly accelerated region 1A/1B [250px-HAR1F_RF00635_rna_secondary_] Predicted secondary structure and sequence conservation of HAR1A Identifiers Symbol HAR1A Rfam RF00635 Other data RNA type Gene; lncRNA Domain Eukaryota; SO SO:0001463 PDB structures PDBe In molecular biology, Human Accelerated Region 1 (Highly Accelerated Region 1, HAR1) is a segment of the human genome found on the long arm of chromosome 20. It is a human accelerated region. It is located within a pair of overlapping long non-coding RNA genes, HAR1A (HAR1F) and HAR1B (HAR1R).^[1] HAR1A [edit] HAR1A is expressed in Cajal-Retzius cells, contemporaneously with the protein reelin.^[1]^[2]^[3] HAR1A was identified in August 2006 when human accelerated regions (HARs) were first investigated. These 49 regions represent parts of the human genome that differ significantly from highly conserved regions of our closest ancestors in terms of evolution. Many of the HARs are associated with genes known to play a role in neurodevelopment. One particularly altered region, HAR1, was found in a stretch of genome with no known protein-coding RNA sequences. Two RNA genes, HAR1F and HAR1R, were identified partly within the region. The RNA structure of HAR1A has been shown to be stable, with a secondary structure unlike those previously described. HAR1A is active in the developing human brain between the 7th and 18th gestational weeks. It is found in the dorsal telencephalon in fetuses. In adult humans, it is found throughout the cerebellum and forebrain; it is also found in the testes.^[1] There is evidence that HAR1 is repressed by REST in individuals with Huntington's disease, perhaps contributing to the neurodegeneration associated with the disease.^[4] Further work on the secondary structure of HAR1A has suggested that the human form adopts a different fold to that of other mammals exemplified by the chimpanzee sequence.^[5] HAR1B [edit] The HAR1B gene overlaps HAR1A, and is located on the opposite strand of the chromosome. Its expression in the human brain is lower than that of HAR1A.^[1] See also [edit] * Non-coding RNA References [edit] 1. ^ ^a ^b ^c ^d Pollard KS, Salama SR, Lambert N, Lambot MA, Coppens S, Pedersen JS, Katzman S, King B, Onodera C, Siepel A, Kern AD, Dehay C, Igel H, Ares M Jr, Vanderhaeghen P, Haussler D (2006-08-16). "An RNA gene expressed during cortical development evolved rapidly in humans" (PDF). Nature. 443 (7108): 167-172. Bibcode:2006Natur.443..167P. doi:10.1038/nature05113. hdl:2013/ ULB-DIPOT:oai:dipot.ulb.ac.be:2013/51805. PMID 16915236. S2CID 18107797. supplement 2. ^ Pollard KS, Salama SR, King B, et al. (October 2006). "Forces shaping the fastest evolving regions in the human genome". PLOS Genet. 2 (10): e168. doi:10.1371/journal.pgen.0020168. PMC 1599772. PMID 17040131. 3. ^ Amadio JP, Walsh CA (September 2006). "Brain evolution and uniqueness in the human genome". Cell. 126 (6): 1033-1035. doi: 10.1016/j.cell.2006.09.007. PMID 16990130. S2CID 16034905. 4. ^ Johnson R, Richter N, Jauch R, Gaughwin PM, Zuccato C, Cattaneo E, Stanton LW (2010). "The Human Accelerated Region 1 noncoding RNA is repressed by REST in Huntington's disease". Physiol Genomics. 41 (3): 269-274. doi:10.1152/physiolgenomics.00019.2010 . PMID 20179156. S2CID 25653037. 5. ^ Beniaminov A, Westhof E, Krol A (July 2008). "Distinctive structures between chimpanzee and human in a brain noncoding RNA" . RNA. 14 (7): 1270-1275. doi:10.1261/rna.1054608. PMC 2441984. PMID 18511501. Further reading [edit] * Scientists Identify Gene Difference Between Humans and Chimps, Scientific American, 17 August 2006 External links [edit] * * Page for Human accelerated region 1F at Rfam * UCSC genome browser page for Human accelerated region 1F * Retrieved from "https://en.wikipedia.org/w/index.php?title= Human_accelerated_region_1&oldid=1317480837" Categories: * Non-coding RNA * Molecular neuroscience * Developmental neuroscience Hidden categories: * Articles with short description * Short description matches Wikidata * Short description is different from Wikidata * This page was last edited on 18 October 2025, at 09:16 (UTC). * Text is available under the Creative Commons Attribution-ShareAlike 4.0 License; additional terms may apply. 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