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, ...

Oncology & Cancer

Twenty four genetic variants linked to heightened womb cancer risk

Twenty four common variations in genes coding for cell growth and death, the processing of oestrogen, and gene control factors may be linked to a heightened risk of developing womb (endometrial) cancer, indicates the most ...

Genetics

Are you 'at risk' of being a habitual tofu eater?

Researchers at the RIKEN Center for Integrative Medical Sciences (IMS) in Japan and colleagues at Osaka University have found genetic variations in humans related to specific dietary habits. Published in Nature Human Behaviour, ...

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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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