Reviewed April 2009
What is chromosome 8?
Humans normally have 46 chromosomes in each cell, divided into 23 pairs. Two copies of chromosome 8, one copy inherited from each parent, form one of the pairs. Chromosome 8 spans more than 146 million DNA building blocks (base pairs) and represents between 4.5 and 5 percent of the total DNA in cells.
Identifying genes on each chromosome is an active area of genetic research. Because researchers use different approaches to predict the number of genes on each chromosome, the estimated number of genes varies. Chromosome 8 likely contains about 700 genes that provide instructions for making proteins. These proteins perform a variety of different roles in the body.
Genes on chromosome 8 are among the estimated 20,000 to 25,000 total genes in the human genome.
Genetics Home Reference includes these genes on chromosome 8:
How are changes in chromosome 8 related to health conditions?
Many genetic conditions are related to changes in particular genes on chromosome 8.
This list of disorders associated with genes on chromosome 8 provides links to additional information.
Genetics Home Reference includes these conditions related to genes on chromosome 8:
- ataxia with vitamin E deficiency
- autosomal dominant nocturnal frontal lobe epilepsy
- Baller-Gerold syndrome
- benign familial neonatal seizures
- branchiootorenal syndrome
- breast cancer
- Charcot-Marie-Tooth disease
- CHARGE syndrome
- Cohen syndrome
- color vision deficiency
- congenital adrenal hyperplasia due to 11-beta-hydroxylase deficiency
- congenital hypothyroidism
- congenital myasthenic syndrome
- epidermolysis bullosa simplex
- epidermolysis bullosa with pyloric atresia
- familial hyperaldosteronism
- familial idiopathic basal ganglia calcification
- familial lipoprotein lipase deficiency
- Farber lipogranulomatosis
- hereditary multiple exostoses
- hereditary spherocytosis
- idiopathic pulmonary fibrosis
- juvenile Paget disease
- Kallmann syndrome
- Klippel-Feil syndrome
- Langer-Giedion syndrome
- mucopolysaccharidosis type III
- Nijmegen breakage syndrome
- Paget disease of bone
- Pfeiffer syndrome
- pyruvate dehydrogenase deficiency
- Roberts syndrome
- Rothmund-Thomson Syndrome
- spastic paraplegia type 8
- surfactant dysfunction
- Waardenburg syndrome
- Werner syndrome
Changes in the structure or number of copies of a chromosome can also cause problems with health and development. The following chromosomal conditions are associated with such changes in chromosome 8.
Rearrangements (translocations) of genetic material between chromosome 8 and other chromosomes have been associated with several types of cancer. For example, Burkitt lymphoma (a cancer of white blood cells that occurs most often in children and young adults) can be caused by a translocation between chromosomes 8 and 14. This translocation, written t(8;14)(q24;q32), leads to continuous cell division without control or order, which likely contributes to the development of Burkitt lymphoma. Less frequently, Burkitt lymphoma can be caused by translocations between chromosomes 8 and 2 or chromosomes 8 and 22.
- Langer-Giedion syndrome
Langer-Giedion syndrome is caused by a deletion or mutation of several genes on the long (q) arm of chromosome 8 at a position described as 8q24.1. The signs and symptoms of this condition are related to the deletion or mutation in at least two genes from this part of the chromosome. Researchers have determined that the loss of a functional EXT1 gene is responsible for the multiple noncancerous (benign) bone tumors called exostoses seen in people with Langer-Giedion syndrome. Loss of a functional TRPS1 gene may cause the other bone and facial abnormalities. One copy of the EXT1 gene and the TRPS1 gene are always missing or mutated in affected individuals; however, neighboring genes may also be involved. The loss of additional genes from this region of chromosome 8 likely contributes to the varied features of Langer-Giedion syndrome.
- recombinant 8 syndrome
Recombinant 8 syndrome is caused by a rearrangement of chromosome 8 that results in a deletion of a piece of the short (p) arm and a duplication of a piece of the long (q) arm. This chromosome abnormality is written rec(8)dup(8q)inv(8)(p23.1q22.1). The signs and symptoms of recombinant 8 syndrome are related to the loss of genetic material on the short arm of chromosome 8 and the presence of extra of genetic material on the long arm of chromosome 8. Researchers are working to determine which genes are involved in the deletion and duplication on chromosome 8.
- other chromosomal conditions
Trisomy 8 occurs when cells have three copies of chromosome 8 instead of the usual two copies. Full trisomy 8, which occurs when all of the body's cells contain an extra copy of chromosome 8, is not compatible with life. A similar but less severe condition called mosaic trisomy 8 occurs when only some of the body's cells have an extra copy of chromosome 8. The signs and symptoms of mosaic trisomy 8 vary widely and can include intellectual disability, absence of the tissue connecting the left and right halves of the brain (corpus callosum), skeletal defects, heart problems, kidney and liver malformations, and facial abnormalities. Trisomy 8 mosaicism is also associated with an increased risk of a specific type of cancer of blood-forming cells called acute myelogenous leukemia.
Another chromosomal condition called inversion duplication 8p is caused by a rearrangement of genetic material on the short (p) arm of chromosome 8. This rearrangement results in an abnormal duplication and an inversion of a segment of the chromosome. An inversion involves the breakage of a chromosome in two places; the resulting piece of DNA is reversed and reinserted into the chromosome. People with inversion duplication 8p typically have severe intellectual disability, a thin or absent corpus callosum, weak muscle tone (hypotonia), abnormal curvature of the spine (scoliosis), and minor facial abnormalities. Some individuals with this condition may also have heart defects, underdeveloped kidneys, or eye abnormalities. Older individuals usually develop abnormal muscle stiffness (spasticity). The signs and symptoms of inversion duplication 8p tend to depend on the size and location of the chromosome segment involved. For example, inclusion of chromosome region 8p21 is thought to be associated with more severe symptoms.
Is there a standard way to diagram chromosome 8?
Geneticists use diagrams called ideograms as a standard representation for chromosomes. Ideograms show a chromosome's relative size and its banding pattern. A banding pattern is the characteristic pattern of dark and light bands that appears when a chromosome is stained with a chemical solution and then viewed under a microscope. These bands are used to describe the location of genes on each chromosome.
See How do geneticists indicate the location of a gene? (http://ghr.nlm.nih.gov/handbook/howgeneswork/genelocation) in the Handbook.
Where can I find additional information about chromosome 8?
You may find the following resources about chromosome 8 helpful. These materials are written for the general public.
- Additional NIH Resources - National Institutes of Health
National Human Genome Research Institute: Chromosome Abnormalities (http://www.genome.gov/11508982)
- Educational resources - Information pages
Atlas of Genetics and Cytogenetics in Oncology and Haematology (http://atlasgeneticsoncology.org/Anomalies/t0814ID1050.html)
- MedlinePlus - Health information
Encyclopedia: Chromosome (http://www.nlm.nih.gov/medlineplus/ency/article/002327.htm)
You may also be interested in these resources, which are designed for genetics professionals and researchers.
Research Resources - Tools for researchers
- Cancer Genetics Web (http://www.cancerindex.org/geneweb/clinkc08.htm)
- Database of Genomic Variants: Chromosome 8 (http://projects.tcag.ca/variation/cgi-bin/tbrowse/tbrowse?source=hg17&table=Locus&show=table&keyword=&flop=AND&fcol=_C19&fcomp==&fkwd=chr8&cols=)
- DNA sequence and analysis of human chromosome 8. Nature. 2006 Jan 19;439(7074):331-5. (http://www.nature.com/nature/journal/v439/n7074/full/nature04406.html)
- Ensembl Human Map View: Chromosome 8 (http://www.ensembl.org/Homo_sapiens/Location/Chromosome?chr=8)
- U.S. Department of Energy: Human Chromosome Launchpad (http://www.ornl.gov/sci/techresources/Human_Genome/launchpad/chrom08.shtml)
- PubMed - Recent literature (http://www.ncbi.nlm.nih.gov/pubmed?term=(Chromosomes,%20Human,%20Pair%208%5BMAJR%5D)%20AND%20(Chromosome%208%5BTI%5D)%20AND%20english%5Bla%5D%20AND%20human%5Bmh%5D%20AND%20%22last%201440%20days%22%5Bdp%5D)
OMIM - Genetic disorder catalog
- BURKITT LYMPHOMA (http://omim.org/entry/113970)
- RECOMBINANT CHROMOSOME 8 SYNDROME (http://omim.org/entry/179613)
- TRICHORHINOPHALANGEAL SYNDROME, TYPE II (http://omim.org/entry/150230)
- Map Viewer - Genetic maps (http://www.ncbi.nlm.nih.gov/mapview/maps.cgi?org=human&maps=ideogr,morbid,pheno&zoom=100&chr=8)
What glossary definitions help with understanding chromosome 8?
acute myelogenous leukemia ;
cell division ;
corpus callosum ;
muscle tone ;
white blood cells
You may find definitions for these and many other terms in the Genetics Home Reference
- Ayakannu T, Wordsworth S, Parveen S, Shehadeh Z, Moselhi M. Rare presentation of Trisomy 8 syndrome. J Obstet Gynaecol. 2008 Oct;28(7):748-9. doi: 10.1080/01443610802462027. (http://www.ncbi.nlm.nih.gov/pubmed/19065376?dopt=Abstract)
- de Die-Smulders CE, Engelen JJ, Schrander-Stumpel CT, Govaerts LC, de Vries B, Vles JS, Wagemans A, Schijns-Fleuren S, Gillessen-Kaesbach G, Fryns JP. Inversion duplication of the short arm of chromosome 8: clinical data on seven patients and review of the literature. Am J Med Genet. 1995 Nov 20;59(3):369-74. Review. (http://www.ncbi.nlm.nih.gov/pubmed/8599364?dopt=Abstract)
- Ensembl Human Map View: Chromosome 8 (http://www.ensembl.org/Homo_sapiens/Location/Chromosome?chr=8)
- Feenstra I, van Ravenswaaij CM, van der Knaap MS, Willemsen MA. Neuroimaging in nine patients with inversion duplication of the short arm of chromosome 8. Neuropediatrics. 2006 Apr;37(2):83-7. (http://www.ncbi.nlm.nih.gov/pubmed/16773506?dopt=Abstract)
- Gilbert F. Chromosome 8. Genet Test. 2001 Winter;5(4):345-54. (http://www.ncbi.nlm.nih.gov/pubmed/11960583?dopt=Abstract)
- Golzio C, Guirchoun J, Ozilou C, Thomas S, Goudefroye G, Morichon-Delvallez N, Vekemans M, Attié-Bitach T, Etchevers HC. Cytogenetic and histological features of a human embryo with homogeneous chromosome 8 trisomy. Prenat Diagn. 2006 Dec;26(13):1201-5. (http://www.ncbi.nlm.nih.gov/pubmed/17075794?dopt=Abstract)
- Graw SL, Sample T, Bleskan J, Sujansky E, Patterson D. Cloning, sequencing, and analysis of inv8 chromosome breakpoints associated with recombinant 8 syndrome. Am J Hum Genet. 2000 Mar;66(3):1138-44. (http://www.ncbi.nlm.nih.gov/pubmed/10712224?dopt=Abstract)
- Hulley BJ, Hummel M, Cook LL, Boyd BK, Wenger SL. Trisomy 8 mosaicism: selective growth advantage of normal cells vs. growth disadvantage of trisomy 8 cells. Am J Med Genet A. 2003 Jan 15;116A(2):144-6. (http://www.ncbi.nlm.nih.gov/pubmed/12494432?dopt=Abstract)
- Map Viewer: Genes on Sequence (http://www.ncbi.nlm.nih.gov/mapview/maps.cgi?ORG=human&MAPS=ideogr,ugHs,genes&CHR=8)
- Merchant S, Schlette E, Sanger W, Lai R, Medeiros LJ. Mature B-cell leukemias with more than 55% prolymphocytes: report of 2 cases with Burkitt lymphoma-type chromosomal translocations involving c-myc. Arch Pathol Lab Med. 2003 Mar;127(3):305-9. Review. (http://www.ncbi.nlm.nih.gov/pubmed/12653573?dopt=Abstract)
- Nusbaum C, Mikkelsen TS, Zody MC, Asakawa S, Taudien S, Garber M, Kodira CD, Schueler MG, Shimizu A, Whittaker CA, Chang JL, Cuomo CA, Dewar K, FitzGerald MG, Yang X, Allen NR, Anderson S, Asakawa T, Blechschmidt K, Bloom T, Borowsky ML, Butler J, Cook A, Corum B, DeArellano K, DeCaprio D, Dooley KT, Dorris L 3rd, Engels R, Glöckner G, Hafez N, Hagopian DS, Hall JL, Ishikawa SK, Jaffe DB, Kamat A, Kudoh J, Lehmann R, Lokitsang T, Macdonald P, Major JE, Matthews CD, Mauceli E, Menzel U, Mihalev AH, Minoshima S, Murayama Y, Naylor JW, Nicol R, Nguyen C, O'Leary SB, O'Neill K, Parker SC, Polley A, Raymond CK, Reichwald K, Rodriguez J, Sasaki T, Schilhabel M, Siddiqui R, Smith CL, Sneddon TP, Talamas JA, Tenzin P, Topham K, Venkataraman V, Wen G, Yamazaki S, Young SK, Zeng Q, Zimmer AR, Rosenthal A, Birren BW, Platzer M, Shimizu N, Lander ES. DNA sequence and analysis of human chromosome 8. Nature. 2006 Jan 19;439(7074):331-5. (http://www.ncbi.nlm.nih.gov/pubmed/16421571?dopt=Abstract)
- Pienkowska-Grela B, Witkowska A, Grygalewicz B, Rymkiewicz G, Rygier J, Woroniecka R, Walewski J. Frequent aberrations of chromosome 8 in aggressive B-cell non-Hodgkin lymphoma. Cancer Genet Cytogenet. 2005 Jan 15;156(2):114-21. (http://www.ncbi.nlm.nih.gov/pubmed/15642390?dopt=Abstract)
- Smith AC, Spuhler K, Williams TM, McConnell T, Sujansky E, Robinson A. Genetic risk for recombinant 8 syndrome and the transmission rate of balanced inversion 8 in the Hispanic population of the southwestern United States. Am J Hum Genet. 1987 Dec;41(6):1083-103. (http://www.ncbi.nlm.nih.gov/pubmed/3687942?dopt=Abstract)
- UCSC Genome Browser: Statistics (http://genome.cse.ucsc.edu/goldenPath/stats.html)
- Voigt R, Gburek-Augustat J, Seidel A, Gillessen-Kaesbach G. Hemihyperplasia and discordant bone age in a patient with trisomy 8 mosaicism. Am J Med Genet A. 2008 Jan 1;146A(1):132-5. (http://www.ncbi.nlm.nih.gov/pubmed/18074372?dopt=Abstract)
The resources on this site should not be used as a substitute for
professional medical care or advice. Users seeking information about
a personal genetic disease, syndrome, or condition should consult with a qualified
See How can I find a genetics professional in my area? (http://ghr.nlm.nih.gov/handbook/consult/findingprofessional) in the Handbook.