Chromosome 5 is one of the 23 pairs of chromosomes in humans. People normally have two copies of this chromosome. Chromosome 5 spans about 182 million base pairs (the building blocks of DNA) and represents almost 6% of the total DNA in cells. Chromosome 5 is the 5th largest human chromosome, yet has one of the lowest gene densities. This is partially explained by numerous gene-poor regions that display a remarkable degree of non-coding and syntenic conservation with non-mammalian vertebrates, suggesting they are functionally constrained.
Because chromosome 5 is responsible for many forms of growth and development (cell divisions) changes may cause cancers. One example would be acute myeloid leukemia (AML).
Genes Number of genes The following are some of the gene count estimates of human chromosome 5. 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 839 — — 2016-09-08 HGNC 790 355 574 2017-05-12 Ensembl 882 1,207 707 2017-03-29 UniProt 875 — — 2018-02-28 NCBI 886 981 785 2017-05-19
Gene list
The following is a partial list of genes on human chromosome 5. For complete list, see the link in the infobox on the right.
Diseases and disorders The following are some of the diseases related to genes located on chromosome 5:
Attention-deficit/hyperactivity disorder Achondrogenesis type 1B Atelosteogenesis, type II Bipolar disorder Bosch-Boonstra-Schaaf optic atrophy syndrome Charcot–Marie–Tooth disease, type 4 Cockayne syndrome Cornelia de Lange syndrome Corneal dystrophy of Bowman layer Cri du chat Diastrophic dysplasia Ehlers–Danlos syndrome Familial adenomatous polyposis Granular corneal dystrophy type I Granular corneal dystrophy type II GM2-gangliosidosis, AB variant Homocystinuria 3-Methylcrotonyl-CoA carboxylase deficiency Myelodysplastic syndrome Netherton syndrome Nicotine dependency Parkinson's disease Primary carnitine deficiency Recessive multiple epiphyseal dysplasia Sandhoff disease Spinal muscular atrophy Sotos Syndrome Survival motor neuron spinal muscular atrophy Treacher Collins syndrome Tricho-hepato-enteric syndrome Usher syndrome
Chromosomal conditions The following conditions are caused by changes in the structure or number of copies of chromosome 5: Cri-du-chat syndrome is caused by a deletion of the end of the short (p) arm of chromosome 5. This chromosomal change is written as 5p-. The signs and symptoms of cri-du-chat syndrome are probably related to the loss of multiple genes in this region. Researchers have not identified all of these genes or determined how their loss leads to the features of the disorder. They have discovered, however, that a larger deletion tends to result in more severe intellectual disability and developmental delays in people with cri-du-chat syndrome.
Researchers have defined narrow regions of the short arm of chromosome 5 that are associated with particular features of cri-du-chat syndrome. A specific region designated 5p15.3 is associated with a cat-like cry, and a nearby region called 5p15.2 is associated with mental retardation, small head (microcephaly), and distinctive facial features. Familial Adenomatous Polyposis is caused by a deletion of the APC tumor suppressor gene on the long (q) arm of chromosome 5. This chromosomal change results in thousands of colonic polyps which gives the patient a 100% risk of colon cancer if total colectomy is not done. Chromosome 5q deletion syndrome is caused by the deletion of the q arm (long arm) of chromosome 5. This deletion has been linked to several blood related disorders including Myelodysplastic syndrome and Erythroblastopenia. This is a different condition than Cri-du-chat which was mentioned above. Other changes in the number or structure of chromosome 5 can have a variety of effects, including delayed growth and development, distinctive facial features, birth defects, and other medical problems. Changes to chromosome 5 include an extra segment of the short (p) or long (q) arm of the chromosome in each cell (partial trisomy 5p or 5q), a missing segment of the long arm of the chromosome in each cell (partial monosomy 5q), and a circular structure called ring chromosome 5. A ring chromosome occurs when both ends of a broken chromosome are reunited.
Cytogenetic band
+ G-bands of human chromosome 5 in resolution 850 bphsGenome Decoration Page, NCBI. Ideogram data for Homo sapience (850 bphs, Assembly GRCh38.p3). Last update 2014-06-03. Retrieved 2017-04-26. 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 5 p 15.33 0 278 gneg 5 p 15.32 278 401 gpos 25 5 p 15.31 401 555 gneg 5 p 15.2 555 802 gpos 50 5 p 15.1 802 972 gneg 5 p 14.3 972 1234 gpos 100 5 p 14.2 1234 1281 gneg 5 p 14.1 1281 1543 gpos 100 5 p 13.3 1543 1836 gneg 5 p 13.2 1836 2068 gpos 25 5 p 13.1 2068 2253 gneg 5 p 12 2253 2407 gpos 50 5 p 11 2407 2592 acen 5 q 11.1 2592 2839 acen 5 q 11.2 2839 3271 gneg 5 q 12.1 3271 3518 gpos 75 5 q 12.2 3518 3580 gneg 5 q 12.3 3580 3765 gpos 75 5 q 13.1 3765 4012 gneg 5 q 13.2 4012 4197 gpos 50 5 q 13.3 4197 4397 gneg 5 q 14.1 4397 4752 gpos 50 5 q 14.2 4752 4907 gneg 5 q 14.3 4907 5400 gpos 100 5 q 15 5400 5678 gneg 5 q 21.1 5678 5879 gpos 100 5 q 21.2 5879 5987 gneg 5 q 21.3 5987 6295 gpos 100 5 q 22.1 6295 6419 gneg 5 q 22.2 6419 6527 gpos 50 5 q 22.3 6527 6666 gneg 5 q 23.1 6666 6943 gpos 100 5 q 23.2 6943 7267 gneg 5 q 23.3 7267 7468 gpos 100 5 q 31.1 7468 7807 gneg 5 q 31.2 7807 8008 gpos 25 5 q 31.3 8008 8316 gneg 5 q 32 8316 8625 gpos 75 5 q 33.1 8625 8887 gneg 5 q 33.2 8887 9072 gpos 50 5 q 33.3 9072 9304 gneg 5 q 34 9304 9690 gpos 100 5 q 35.1 9690 9952 gneg 5 q 35.2 9952 10183 gpos 25 5 q 35.3 10183 10600 gneg
References
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