Chromosome 8 (human)
Encyclopedia
Chromosome 8 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 8 spans about 145 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 4.5 and 5.0% 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....
.
The chromosome has two arms, 8p and 8q. The short arm, 8p, has about 45 million base pairs, about 1.5% of the genome, and includes 484 genes and 110 pseudogene
Pseudogene
Pseudogenes are dysfunctional relatives of known genes that have lost their protein-coding ability or are otherwise no longer expressed in the cell...
s; about 8% of its genes are involved in brain development and function, and about 16% are involved in cancer
Cancer
Cancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...
. A unique feature of 8p is a big region of about 15 megabases that appears to have a high mutation rate, and which shows an immense divergence between human and chimpanzee
Chimpanzee
Chimpanzee, sometimes colloquially chimp, is the common name for the two extant species of ape in the genus Pan. The Congo River forms the boundary between the native habitat of the two species:...
, suggesting that its high mutation rates have contributed to the evolution of the human brain.
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 8 is likely to contain between 700 and 1,000 genes.
Genes
The following are some of the genes located on chromosome 8:- AEG1 : Astrocyte Elevated Gene (linked to hepatocellular carcinoma and neuroblastoma)
- Arc/Arg3.1Arc (protein)Arc, for activity-regulated cytoskeleton-associated protein , is a plasticity protein first characterized in 1995. Arc is a member of the immediate-early gene family, a rapidly activated class of genes functionally defined by their ability to be transcribed in the presence of protein synthesis...
- FGFR1: fibroblast growth factorFibroblast growth factorFibroblast growth factors, or FGFs, are a family of growth factors involved in angiogenesis, wound healing, and embryonic development. The FGFs are heparin-binding proteins and interactions with cell-surface associated heparan sulfate proteoglycans have been shown to be essential for FGF signal...
receptor 1 (fms-related tyrosine kinase 2, Pfeiffer syndromePfeiffer syndromePfeiffer syndrome is a rare genetic disorder characterized by the premature fusion of certain bones of the skull , which prevents further growth of the skull and affects the shape of the head and face...
) - GDAP1GDAP1Ganglioside-induced differentiation-associated protein 1 is a protein that in humans is encoded by the GDAP1 gene.-External links:* * *...
: ganglioside-induced differentiation-associated protein 1 - LPLLipoprotein lipaseLipoprotein lipase is a member of the lipase gene family, which includes pancreatic lipase, hepatic lipase, and endothelial lipase. It is a water soluble enzyme that hydrolyzes triglycerides in lipoproteins, such as those found in chylomicrons and very low-density lipoproteins , into two free...
: lipoprotein lipaseLipoprotein lipaseLipoprotein lipase is a member of the lipase gene family, which includes pancreatic lipase, hepatic lipase, and endothelial lipase. It is a water soluble enzyme that hydrolyzes triglycerides in lipoproteins, such as those found in chylomicrons and very low-density lipoproteins , into two free... - MCPH1MicrocephalinMicrocephalin is one of six genes causing primary microcephaly when non-functional mutations exist in the homozygous state...
: microcephalyMicrocephalyMicrocephaly is a neurodevelopmental disorder in which the circumference of the head is more than two standard deviations smaller than average for the person's age and sex. Microcephaly may be congenital or it may develop in the first few years of life...
, primary autosomal recessive 1 - NDRG1NDRG1Protein NDRG1 is a protein that in humans is encoded by the NDRG1 gene.It has been reported that NDRG1 localizes to the endosomes and is a Rab4a effector involved in vesicular recycling.-External links:*...
: N-myc downstream regulated gene 1 - NEF3: neurofilament 3 (150kDa medium)
- NEFLNEFLNeurofilament light polypeptide is a protein that in humans is encoded by the NEFL gene.It is associated with Charcot–Marie–Tooth disease 1F and 2E.-Interactions:NEFL has been shown to interact with MAP2, Protein kinase N1 and TSC1....
: neurofilament, light polypeptide 68kDa - SNAI2SNAI2Zinc finger protein SNAI2 is a protein that in humans is encoded by the SNAI2 gene.-Further reading:...
: snail homolog 2 (Drosophila) - TGThyroglobulinThyroglobulin is a 660 kDa, dimeric protein produced by and used entirely within the thyroid gland. In earlier literature, Tg was referred to as colloid....
: thyroglobulinThyroglobulinThyroglobulin is a 660 kDa, dimeric protein produced by and used entirely within the thyroid gland. In earlier literature, Tg was referred to as colloid.... - TPATissue plasminogen activatorTissue plasminogen activator is a protein involved in the breakdown of blood clots. It is a serine protease found on endothelial cells, the cells that line the blood vessels. As an enzyme, it catalyzes the conversion of plasminogen to plasmin, the major enzyme responsible for clot breakdown...
: tissue plasminogen activatorTissue plasminogen activatorTissue plasminogen activator is a protein involved in the breakdown of blood clots. It is a serine protease found on endothelial cells, the cells that line the blood vessels. As an enzyme, it catalyzes the conversion of plasminogen to plasmin, the major enzyme responsible for clot breakdown... - VMAT1VMAT1VMAT1 is a protein that transports the monoamines into intracellular vesicles.In chromaffin cells, it is responsible for transporting newly synthesized epinephrine from the cytosol back into chromaffin granules in preparation for release.For norepinephrine to be acted upon by PNMT in the cytosol,...
: vesicular monoamine transporterVesicular monoamine transporterThe vesicular monoamine transporter is a transport protein integrated into the membrane of intracellular vesicles of presynaptic neurons. It acts to transport monoamines into the synaptic vesicles.-Monoamines:...
protein - WRNWRN (gene)WRN is a human gene that provides instructions for producing Werner protein, which is a type of enzyme called a helicase. Helicase enzymes generally unwind and separate double-stranded DNA. These activities are necessary before DNA can be copied in preparation for cell division...
: Werner syndromeWerner syndromeWerner syndrome is a very rare, autosomal recessive disorder characterized by the appearance of premature aging.... - GULOPL-gulonolactone oxidaseL-gulonolactone oxidase is an enzyme that catalyzes the reaction of D-glucuronolactone with oxygen to L-xylo-hex-3-gulonolactone and hydrogen peroxide. It uses FAD as a cofactor...
pseudogene: responsible for human inability to produce our own Vitamin C
Diseases & disorders
The following diseases are some of those related to genes on chromosome 8:- 8p23.1 duplication syndrome8p23.1 duplication syndrome8p23.1 duplication syndrome is a rare genetic disorder caused by a duplication of a region from human chromosome 8. This duplication syndrome has an estimated prevalence of 1 in 64,000 births and is the reciprocal of the 8p23.1 deletion syndrome...
- Burkitt's lymphomaBurkitt's lymphomaBurkitt's lymphoma is a cancer of the lymphatic system...
- Charcot-Marie-Tooth diseaseCharcot-Marie-Tooth diseaseCharcot–Marie–Tooth disease- , known also as Morbus Charcot-Marie-Tooth, Charcot-Marie-Tooth neuropathy, hereditary motor and sensory neuropathy , hereditary sensorimotor neuropathy , or peroneal muscular atrophy, is an inherited disorder of nerves that takes different forms...
- Charcot-Marie-Tooth disease, type 2
- Charcot-Marie-Tooth disease, type 4
- Cleft lip and palate
- Cohen syndromeCohen syndromeCohen syndrome is believed to be a gene mutation at locus 8q22 gene COH1. Cohen syndrome has several characteristics such as obesity, mental retardation and craniofacial dysmorphism...
- Congenital hypothyroidismCongenital hypothyroidismCongenital hypothyroidism is a condition of thyroid hormone deficiency present at birth. Approximately 1 in 4000 newborn infants has a severe deficiency of thyroid function, while even more have mild or partial degrees. If untreated for several months after birth, severe congenital hypothyroidism...
- Lipoprotein lipase deficiency, familial
- Primary microcephalyMicrocephalyMicrocephaly is a neurodevelopmental disorder in which the circumference of the head is more than two standard deviations smaller than average for the person's age and sex. Microcephaly may be congenital or it may develop in the first few years of life...
- Hereditary Multiple ExostosesHereditary multiple exostosesHereditary multiple exostoses is a rare medical condition in which multiple bony spurs or lumps develop on the bones of a child...
- Pfeiffer syndromePfeiffer syndromePfeiffer syndrome is a rare genetic disorder characterized by the premature fusion of certain bones of the skull , which prevents further growth of the skull and affects the shape of the head and face...
- Rothmund-Thomson syndrome, or poikiloderma congenitale
- SchizophreniaSchizophreniaSchizophrenia is a mental disorder characterized by a disintegration of thought processes and of emotional responsiveness. It most commonly manifests itself as auditory hallucinations, paranoid or bizarre delusions, or disorganized speech and thinking, and it is accompanied by significant social...
, associated with 8p21-22 locus - 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...
- Werner syndromeWerner syndromeWerner syndrome is a very rare, autosomal recessive disorder characterized by the appearance of premature aging....
- Pingelapese blindness
- Langer-Giedion syndromeLanger-Giedion syndromeLanger-Giedion syndrome , also called trichorhinophalangeal syndrome type II or LGCR , is a very uncommon autosomal dominant genetic disorder caused by a deletion of chromosomal material. It is named after the two doctors who undertook the main research into the condition in the 1960s...
- Roberts SyndromeRoberts syndromeRoberts syndrome, or sometimes called pseudothalidomide syndrome, is an extremely rare genetic disorder that is characterized by mild to severe prenatal retardation or disruption of cell division, leading to malformation of the bones in the skull, face, arms, and legs.Roberts syndrome is also known...