Cardiology

Family history doubles aortic stenosis risk

The risk of aortic stenosis doubles when a first degree relative had the disease, according to research presented at ESC Congress 2013 today by Dr. Mattis F. Ranthe from Denmark. The study of 4.2 million people from Danish ...

Genetics

Study finds new genetic risk markers in pancreatic cancer

A large DNA analysis of people with and without pancreatic cancer has identified several new genetic markers that signal increased risk of developing the highly lethal disease, report scientists from Dana-Farber Cancer Institute.

Genetics

Friendship may have a genetic component

(PhysOrg.com) -- New research suggests groups of friends may have common genetic patterns. Social scientist Professor James Fowler of the University of California, San Diego, came to this conclusion after looking at data ...

Genetics

The influence of genetics on nutritional requirements

Approximately 0.1%: that is the average genetic difference between two individuals. This small percentage is responsible for the variations of certain physical traits, such as eyes, hair, and height, but also for differences ...

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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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