Chromosome 8 is one of the 23 pairs of chromosomes in humans. People normally have two copies of this chromosome. Chromosome 8 spans about 146 million base pairs (the building material of DNA) and represents between 4.5 and 5.0% of the total DNA in cells.
About 8% of its genes are involved in brain development and function, and about 16% are involved in cancer. A unique feature of 8p is a region of about 15 megabases that appears to have a high mutation rate. This region shows a significant divergence between human and chimpanzee, suggesting that its high mutation rates have contributed to the evolution of the human brain.
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Genes Number of genes The following are some of the gene count estimates of human chromosome 8. Because researchers use different approaches to genome annotation their predictions of the number of genes on each chromosome varies (for technical details, see gene prediction). Among various projects, the collaborative consensus coding sequence project (CCDS) takes an extremely conservative strategy. So CCDS's gene number prediction represents a lower bound on the total number of human protein-coding genes.
Estimated by Protein-coding genes Non-coding RNA genes Pseudogenes Source Release date CCDS 646 — — 2016-09-08 HGNC 656 242 539 2017-05-12 Ensembl 670 1,052 613 2017-03-29 UniProt 703 — — 2018-02-28 NCBI 719 848 682 2017-05-19
Gene list
The following is a partial list of genes on human chromosome 8. For complete list, see the link in the infobox on the right.
Diseases and disorders The following diseases and disorders are some of those related to genes on chromosome 8:
8p23.1 duplication syndrome Bipolar disorder Burkitt lymphoma Charcot–Marie–Tooth disease COACH syndrome Cleft lip and cleft palate Cohen syndrome Congenital hypothyroidism Fahr's syndrome Hereditary multiple exostoses Lipoprotein lipase deficiency, familial Monosomy 8p Myelodysplastic syndrome Pfeiffer syndrome Primary microcephaly Rothmund–Thomson syndrome Schizophrenia, associated with 8p21-22 locus Waardenburg syndrome Werner syndrome Pingelapese blindness Langer–Giedion syndrome Roberts syndrome Hepatocellular carcinoma Sanfilippo syndrome
Rearrangements involving the short arm of Chromosome 8 (8p) can be highly variable in size and gene content, resulting in a wide range of phenotypes including epilepsy, autism, hypotonia, gastrointestinal dysfunction, and congenital heart defects. Project 8p Foundation, a global nonprofit patient advocacy organization, supports individuals affected by chromosome 8p disorders, through community support and connection, a longitudinal natural history study, biorepository, open-access data platform, and the development of precision medicine tools aimed at improving clinical care and accelerating discovery. There is also a multidisciplinary clinic for 8p rearrangements led by Project 8p available to affected families.
Cytogenetic band
+ G-bands of human chromosome 8 in resolution 850 bphs Chr. Arm"p": Short arm; "q": Long arm. BandFor cytogenetic banding nomenclature, see article locus. ISCNstartThese values (ISCN start/stop) are based on the length of bands/ideograms from the ISCN book, An International System for Human Cytogenetic Nomenclature (2013). Arbitrary unit. ISCNstop Basepairstart Basepairstop Staingpos: Region which is positively stained by G banding, generally AT-rich and gene poor; gneg: Region which is negatively stained by G banding, generally CG-rich and gene rich; acen Centromere. var: Variable region; stalk: Stalk. Density 8 p 23.3 0 115 gneg 8 p 23.2 115 331 gpos 75 8 p 23.1 331 690 gneg 8 p 22 690 992 gpos 100 8 p 21.3 992 1179 gneg 8 p 21.2 1179 1380 gpos 50 8 p 21.1 1380 1639 gneg 8 p 12 1639 1897 gpos 75 8 p 11.23 1897 2041 gneg 8 p 11.22 2041 2156 gpos 25 8 p 11.21 2156 2343 gneg 8 p 11.1 2343 2472 acen 8 q 11.1 2472 2645 acen 8 q 11.21 2645 2817 gneg 8 q 11.22 2817 3033 gpos 75 8 q 11.23 3033 3277 gneg 8 q 12.1 3277 3493 gpos 50 8 q 12.2 3493 3622 gneg 8 q 12.3 3622 3809 gpos 50 8 q 13.1 3809 3938 gneg 8 q 13.2 3938 4096 gpos 50 8 q 13.3 4096 4312 gneg 8 q 21.11 4312 4545 gpos 100 8 q 21.12 4545 4628 gneg 8 q 21.13 4628 4858 gpos 75 8 q 21.2 4858 4959 gneg 8 q 21.3 4959 5289 gpos 100 8 q 22.1 5289 5577 gneg 8 q 22.2 5577 5692 gpos 25 8 q 22.3 5692 5922 gneg 8 q 23.1 5922 6152 gpos 75 8 q 23.2 6152 6267 gneg 8 q 23.3 6267 6611 gpos 100 8 q 24.11 6611 6726 gneg 8 q 24.12 6726 6942 gpos 50 8 q 24.13 6942 7244 gneg 8 q 24.21 7244 7431 gpos 50 8 q 24.22 7431 7661 gneg 8 q 24.23 7661 7804 gpos 75 8 q 24.3 7804 8250 gneg
References
External links