Showing posts with label SNPs. Show all posts
Showing posts with label SNPs. Show all posts

Tuesday, April 14, 2009

Single Nucleotide Polymorphisms

Single Nucleotide Polymorphisms (SNPs) are the variations in a DNA sequence in comparison to the conventional sequence of the DNA of that particular species.

Single Nucleotide Polymorphisms can fall anywhere in a genomic DNA. They can be found in the coding region, non-coding region and in between the coding and non-coding regions of DNA.

The Single Nucleotide Polymorphisms which fall in the coding region of the DNA have a great importance. Since they can make a huge difference in functioning of the particular gene falling in the coding region, they are closely observed and analyzed. For example, if a single nucleotide polymorphism changes the protein code of the gene, it will no longer make the same product of the protein. If it happens it is said that a mutation has occurred in the gene. If the mutation is severe it could result in a form of a disease. Usually cancers develop in this fashion. According to scientists at least seven SNP mutations are required in a functional gene to develop cancer.

If the mutation is not severe, it could be benign or have some affect on the behavior of the individual. For example, a human being with one type of Single Nucleotide Polymorphism mutation might not be able to tolerate a certain medication as compared to it's counterparts in the same population.