Oncology & Cancer

Study of NCOA3 yields novel findings of melanoma progression

For the first time, activation of nuclear receptor coactivator 3 (NCOA3) has been shown to promote the development of melanoma through regulation of ultraviolet radiation (UVR) sensitivity, cell cycle progression and circumvention ...

Genetics

Induced pluripotent stem cells reveal causes of disease

Induced pluripotent stem cells (iPSC) are suitable for discovering the genes that underly complex, rare genetic diseases. Scientists from the German Cancer Research Center (DKFZ) and the European Molecular Biology Laboratory ...

Diseases, Conditions, Syndromes

Scientists demonstrate how genetic variations cause eczema

New research supported by the National Institutes of Health delineates how two relatively common variations in a gene called KIF3A are responsible for an impaired skin barrier that allows increased water loss from the skin, ...

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Single-nucleotide polymorphism

A single-nucleotide polymorphism (SNP, pronounced snip) is a DNA sequence variation occurring when a single nucleotide — A, T, C, or G — in the genome (or other shared sequence) differs between members of a species (or between paired chromosomes in an individual). For example, two sequenced DNA fragments from different individuals, AAGCCTA to AAGCTTA, contain a difference in a single nucleotide. In this case we say that there are two alleles : C and T. Almost all common SNPs have only two alleles.

Within a population, SNPs can be assigned a minor allele frequency — the lowest allele frequency at a locus that is observed in a particular population. This is simply the lesser of the two allele frequencies for single-nucleotide polymorphisms[1]. There are variations between human populations, so a SNP allele that is common in one geographical or ethnic group may be much rarer in another.

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