Chromosome 8 is one of the 23 pairs of

chromosome A chromosome is a package of DNA containing part or all of the genetic material of an organism. In most chromosomes, the very long thin DNA fibers are coated with nucleosome-forming packaging proteins; in eukaryotic cells, the most import ...

s in

human Humans (''Homo sapiens'') or modern humans are the most common and widespread species of primate, and the last surviving species of the genus ''Homo''. They are Hominidae, great apes characterized by their Prehistory of nakedness and clothing ...

s. People normally have two copies of this chromosome. Chromosome 8 spans about 146 million

base pair A base pair (bp) is a fundamental unit of double-stranded nucleic acids consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix and contribute to the folded structure of both DNA ...

s (the building material of

DNA Deoxyribonucleic acid (; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of al ...

) and represents between 4.5 and 5.0% of the total DNA in cells. About 8% of its genes are involved in

brain development The brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It consists of nervous tissue and is typically located in the head ( cephalization), usually near organs for special sens ...

and function, and about 16% are involved in

cancer Cancer is a group of diseases involving Cell growth#Disorders, abnormal cell growth with the potential to Invasion (cancer), invade or Metastasis, spread to other parts of the body. These contrast with benign tumors, which do not spread. Po ...

. A unique feature of 8p is a region of about 15 megabases that appears to have a high

mutation rate In genetics, the mutation rate is the frequency of new mutations in a single gene, nucleotide sequence, or organism over time. Mutation rates are not constant and are not limited to a single type of mutation; there are many different types of mu ...

. This region shows a significant divergence between human and

chimpanzee The chimpanzee (; ''Pan troglodytes''), also simply known as the chimp, is a species of Hominidae, great ape native to the forests and savannahs of tropical Africa. It has four confirmed subspecies and a fifth proposed one. When its close rel ...

, suggesting that its high mutation rates have contributed to the evolution of the human brain. __TOC__

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 In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: prote ...

on each chromosome varies (for technical details, see

gene prediction In computational biology, gene prediction or gene finding refers to the process of identifying the regions of genomic DNA that encode genes. This includes protein-coding genes as well as RNA genes, but may also include prediction of other functio ...

). 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.

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 Bipolar disorder (BD), previously known as manic depression, is a mental disorder characterized by periods of Depression (mood), depression and periods of abnormally elevated Mood (psychology), mood that each last from days to weeks, and in ...

Burkitt lymphoma Burkitt's lymphoma is a cancer of the lymphatic system, particularly B lymphocytes found in the germinal center. It is named after Denis Parsons Burkitt, the Irish surgeon who first described the disease in 1958 while working in equatorial Africa ...

* Charcot–Marie–Tooth disease * COACH syndrome * Cleft lip and cleft palate * Cohen syndrome *

Congenital hypothyroidism Congenital hypothyroidism (CH) is thyroid hormone deficiency present at birth. If untreated for several months after birth, severe congenital hypothyroidism can lead to growth failure and permanent intellectual disability. Infants born with co ...

* Fahr's syndrome *

Hereditary multiple exostoses Hereditary multiple osteochondromas (HMO), also known as hereditary multiple exostoses, is a disorder characterized by the development of multiple benign osteocartilaginous masses (exostosis, exostoses) in relation to the ends of long bones of t ...

* Lipoprotein lipase deficiency, familial * Monosomy 8p *

Myelodysplastic syndrome A myelodysplastic syndrome (MDS) is one of a group of cancers in which blood cells in the bone marrow do not mature, and as a result, do not develop into healthy blood cells. Early on, no symptoms typically are seen. Later, symptoms may includ ...

Pfeiffer syndrome Pfeiffer syndrome is a rare genetic disorder, characterized by the premature fusion of certain bones of the human skull, skull (craniosynostosis), which affects the shape of the head and face. The syndrome includes abnormalities of the hands an ...

* Primary

microcephaly Microcephaly (from Neo-Latin ''microcephalia'', from Ancient Greek μικρός ''mikrós'' "small" and κεφαλή ''kephalé'' "head") is a medical condition involving a smaller-than-normal head. Microcephaly may be present at birth or it m ...

* Rothmund–Thomson syndrome *

Schizophrenia Schizophrenia () is a mental disorder characterized variously by hallucinations (typically, Auditory hallucination#Schizophrenia, hearing voices), delusions, thought disorder, disorganized thinking and behavior, and Reduced affect display, f ...

, associated with 8p21-22 locus *

Waardenburg syndrome Waardenburg syndrome is a group of rare genetic conditions characterised by at least some degree of congenital hearing loss and pigmentation deficiencies, which can include bright blue eyes (or Heterochromia iridum, one blue eye and one brown ey ...

* Werner syndrome * Pingelapese blindness * Langer–Giedion syndrome * Roberts syndrome *

Hepatocellular carcinoma Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer in adults and is currently the most common cause of death in people with cirrhosis. HCC is the third leading cause of cancer-related deaths worldwide. HCC most common ...

* Sanfilippo syndrome

Cytogenetic band

References

* *

External links

* * {{DEFAULTSORT:Chromosome 08 (Human) Chromosomes (human) *