The human genome is the genome of Homo sapiens.
It is made up of 23 chromosome pairs with a total of about 3 billion DNA base pairs.
There are 24 distinct human chromosomes: 22 autosomal chromosomes, plus the sex-determining X and Y chromosomes.
Chromosomes 1-22 are numbered roughly in order of decreasing size.
Somatic cells usually have one copy of chromosomes 1-22 from each parent, plus an X chromosome from the mother, and either an X or Y chromosome from the father, for a total of 46.
There are an estimated 20,000-25,000 human protein-coding genes.
The estimate of the number of human genes has been repeatedly revised down from initial predictions of 100,000 or more as genome sequence quality and gene finding methods have improved, and could continue to drop further.
Somatic cell A somatic cell is generally taken to mean any cell forming the body of an organism. Somatic cells, by definition, are not germline cells. In mammals, ... >
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Chromosome The DNA which carries genetic information in cells is normally packaged in the form of one or more large macromolecules called chromosomes. A ... >
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Mitosis In biology, mitosis is the process by which a cell separates its duplicated genome into two identical halves. It is generally followed immediately by ... >
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Human Genome Project The Human Genome Project (HGP) endeavoured to map the human genome down to the nucleotide (or base pair) level and to identify all the genes present ... >
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Allele An allele is a viable DNA (deoxyribonucleic acid) coding that occupies a given locus (position) on a chromosome. Usually alleles are sequences that ... >
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BRCA2 BRCA2 is a human gene that is involved in the repair of chromosomal damage and belongs to a class of genes known as tumor suppressor genes. Tumor ... >
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Gene A gene is a locatable region of genomic sequence, corresponding to a unit of inheritance, which is associated with regulatory regions, transcribed ... >
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Sex linkage Sex linkage is the phenotypic expression of an allele that is dependent on the gender of the individual and is directly tied to the sex chromosomes. ... >
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BRCA1 BRCA1 (breast cancer 1, early onset) is a human gene that belongs to a class of genes known as tumor suppressor genes. Like many other tumor ... >
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Trait (biology) In biology, a trait or character is a feature of an organism. The term phenotype is sometimes used as a synonym for trait in common use, but strictly ... >
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