Chromosome 13 (human)
Encyclopedia
Chromosome 13 is one of the 23 pairs of chromosome
Chromosome
A chromosome is an organized structure of DNA and protein found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions.Chromosomes...
s in human
Human
Humans are the only living species in the Homo genus...
s. People normally have two copies of this chromosome. Chromosome 13 spans about 114 million base pair
Base pair
In molecular biology and genetics, the linking between two nitrogenous bases on opposite complementary DNA or certain types of RNA strands that are connected via hydrogen bonds is called a base pair...
s (the building material of DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
) and represents between 3.5 and 4 % of the total DNA in cells
Cell (biology)
The cell is the basic structural and functional unit of all known living organisms. It is the smallest unit of life that is classified as a living thing, and is often called the building block of life. The Alberts text discusses how the "cellular building blocks" move to shape developing embryos....
.
Identifying gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
s 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 13 likely contains between 300 and 700 genes.
Genes
The following are some of the genes located on chromosome 13:- ATP7B: ATPase, Cu++ transporting, beta polypeptide (Wilson disease)
- BRCA2BRCA2BRCA2 is a protein that in humans is encoded by the BRCA2 gene.BRCA2 orthologs have been identified in most mammals for which complete genome data are available....
: breast cancer 2, early onset - CARKDCARKDCarbohydrate kinase domain containing protein, also known as CARKD, is a human protein of unknown function. The protein is conserved throughout many species, and has predicted orthologs through eukaryotes, bacteria, and archea.- Gene :...
: Carbohydrate Kinase Domain Containing Protein (Unknown Function) - EDNRBEndothelin receptor type BEndothelin receptor type B, also known as ETB is a protein that in humans is encoded by the EDNRB gene.- Function :Endothelin receptor type B is a G protein-coupled receptor which activates a phosphatidylinositol-calcium second messenger system. Its ligand, endothelin, consists of a family of three...
: endothelin receptor type B - GJB2GJB2Gap junction beta-2 also known as connexin-26 is a protein that in humans is encoded by the GJB2 gene. Defects in this gene lead to the most common form of congenital deafness in developed countries, called DFNB1, also known as Connexin 26 deafness or GJB2-related deafness.- Function :Gap...
: gap junction protein, beta 2, 26kDa (connexin 26) - GJB6: gap junction protein, beta 6 (connexin 30)
- HTR2A: 5-HT2A receptor
- PCCA: propionyl Coenzyme A carboxylase, alpha polypeptide
- RB1: retinoblastoma 1 (including osteosarcoma)
- FLT1FLT1Vascular endothelial growth factor receptor 1 is a protein that in humans is encoded by the FLT1 gene.-Interactions:FLT1 has been shown to interact with PLCG1 and Vascular endothelial growth factor B.-Further reading:...
: Fms related tyrosine kinase 1 (Vascular endothelial growth factorVascular endothelial growth factorVascular endothelial growth factor is a signal protein produced by cells that stimulates vasculogenesis and angiogenesis. It is part of the system that restores the oxygen supply to tissues when blood circulation is inadequate....
receptor 1) - SLITRK1SLITRK1SLITRK1 is a human gene on chromosome 13q31.1. In 2005, medical researchers observed a de novo chromosomal abnormality in a patient with Tourette syndrome which broke the patient's chromosome near SLITRK1...
: mutation in this gene causes some (although very few) cases of Tourette syndromeTourette syndromeTourette syndrome is an inherited neuropsychiatric disorder with onset in childhood, characterized by multiple physical tics and at least one vocal tic; these tics characteristically wax and wane...
and trichotillomaniaTrichotillomaniaTrichotillomania, which is classified as an impulse control disorder by DSM-IV, is the compulsive urge to pull out one's own hair leading to noticeable hair loss, distress, and social or functional impairment. It is often chronic and difficult to treat.... - SOX21SOX21Transcription factor SOX-21 is a protein that in humans is encoded by the SOX21 gene. It is a member of the Sox gene family of transcription factors.- Function :...
: Transcription factor SOX-21 is a proteinProteinProteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
that in humans is encoded by the SOX21; its disruption can lead to types of alopeciaAlopeciaAlopecia means loss of hair from the head or body. Alopecia can mean baldness, a term generally reserved for pattern alopecia or androgenic alopecia. Compulsive pulling of hair can also produce hair loss. Hairstyling routines such as tight ponytails or braids may induce Traction alopecia. Both...
in mice.
Diseases and disorders
The following diseases are some of those related to genes on chromosome 13:- Bladder cancerBladder cancerBladder cancer is any of several types of malignant growths of the urinary bladder. It is a disease in which abnormal cells multiply without control in the bladder. The bladder is a hollow, muscular organ that stores urine; it is located in the pelvis...
- Breast cancerBreast cancerBreast cancer is cancer originating from breast tissue, most commonly from the inner lining of milk ducts or the lobules that supply the ducts with milk. Cancers originating from ducts are known as ductal carcinomas; those originating from lobules are known as lobular carcinomas...
- HeterochromiaHeterochromiaIn anatomy, heterochromia refers to a difference in coloration, usually of the iris but also of hair or skin. Heterochromia is a result of the relative excess or lack of melanin...
- Hirschsprung's diseaseHirschsprung's diseaseHirschsprung's disease , or congenital aganglionic megacolon is a serious medical problem where the enteric nervous system is missing from the end of the bowel. The enteric nervous system is a complex network of neurons and glia that controls most aspects of intestinal function...
- Maturity onset diabetes of the youngMaturity onset diabetes of the youngMaturity onset diabetes of the young refers to any of several hereditary forms of diabetes caused by mutations in an autosomal dominant gene disrupting insulin production...
type 4 - Nonsyndromic deafnessNonsyndromic deafnessNonsyndromic deafness is hearing loss that is not associated with other signs and symptoms. In contrast, syndromic deafness involves hearing loss that occurs with abnormalities in other parts of the body....
- Nonsyndromic deafness, autosomal dominant
- Nonsyndromic deafness, autosomal recessive
- Propionic acidemiaPropionic acidemiaPropionic acidemia, also known as propionic aciduria, propionyl-CoA carboxylase deficiency and ketotic glycinemia, is an autosomal recessive metabolic disorder, classified as a branched-chain organic acidemia....
- RetinoblastomaRetinoblastomaRetinoblastoma is a rapidly developing cancer that develops in the cells of retina, the light-detecting tissue of the eye. In the developed world, Rb has one of the best cure rates of all childhood cancers , with more than nine out of every ten sufferers surviving into...
- Waardenburg syndromeWaardenburg syndromeWaardenburg syndrome Waardenburg syndrome Waardenburg syndrome (also Waardenburg Shah Syndrome, Waardenburg-Klein syndrome, Mende's syndrome II, Van der Hoeve-Halbertsma-Waardenburg syndrome, Ptosis-Epicanthus syndrome, Van der Hoeve-Halbertsma-Gualdi syndrome, Waardenburg type Pierpont,[5] Van...
- Wilson's diseaseWilson's diseaseWilson's disease or hepatolenticular degeneration is an autosomal recessive genetic disorder in which copper accumulates in tissues; this manifests as neurological or psychiatric symptoms and liver disease...
- Patau syndromePatau syndromePatau syndrome, also known as trisomy 13 and trisomy D, is a chromosomal abnormality, a syndrome in which a patient has an additional chromosome 13 due to a nondisjunction of chromosomes during meiosis. Some are caused by Robertsonian translocations...
Chromosomal conditions
The following conditions are caused by changes in the structure or number of copies of chromosome 13:- RetinoblastomaRetinoblastomaRetinoblastoma is a rapidly developing cancer that develops in the cells of retina, the light-detecting tissue of the eye. In the developed world, Rb has one of the best cure rates of all childhood cancers , with more than nine out of every ten sufferers surviving into...
: A small percentage of retinoblastoma cases are caused by deletions in the region of chromosome 13 (13q14) containing the RB1 gene. Children with these chromosomal deletions may also have mental retardation, slow growth, and characteristic facial features (such as prominent eyebrows, a broad nasal bridge, a short nose, and ear abnormalities). Researchers have not determined which other genes are located in the deleted region, but a loss of several genes is likely responsible for these developmental problems. - Trisomy 13: Trisomy 13 occurs when each cell in the body has three copies of chromosome 13 instead of the usual two copies. Trisomy 13 can also result from an extra copy of chromosome 13 in only some of the body's cells (mosaic trisomy 13). In a small percentage of cases, trisomy 13 is caused by a rearrangement of chromosomal material between chromosome 13 and another chromosome. As a result, a person has the two usual copies of chromosome 13, plus extra material from chromosome 13 attached to another chromosome. These cases are called translocation trisomy 13. Extra material from chromosome 13 disrupts the course of normal development, causing the characteristic signs and symptoms of trisomy 13. Researchers are not yet certain how this extra genetic material leads to the features of the disorder, which include severely abnormal cerebral functions, a small cranium, retardation, non functional eyes and heart defects.
- Other chromosomal conditions: Partial monosomy 13qPartial monosomy 13qPartial Monosomy of chromosome 13q, can be defined as the loss of or physical deletion of the long arm of chromosome 13 in human beings. This is a rare genetic disorder which can result in unusual abnormalities in which the sufferer most often dies at an improbable age. There are other symptoms,...
is a rare chromosomal disorder that results when a piece of the long arm (q) of chromosome 13 is missing (monosomic). Infants born with partial monosomy 13q may exhibit low birth weight, malformations of the head and face (craniofacial region), skeletal abnormalities (especially of the hands and feet), and other physical abnormalities. Mental retardation is characteristic of this condition. The mortality rate during infancy is high among individuals born with this disorder. Almost all cases of partial monosomy 13q occur randomly for no apparent reason (sporadic).