Single nucleotide polymorphisms (SNPs) are variations in DNA base pairs between individuals. They can impact genome expression and are used in genetic fingerprinting and medical research to tailor treatments and highlight disease risks.
Single nucleotide polymorphisms (SNPs) are single variations in the base pairs of deoxyribonucleic acid (DNA) between individuals. There are four nucleotides in DNA: Guanine (G), Adenine (A), Thymine (T), and Cytosine (C), which can combine in a variety of ways to build genetic blueprints for making proteins, regulating gene expression, and other activities. In people with single nucleotide polymorphisms, one of them is swapped. The rest of the DNA strand should be identical, such as a chain like CCATCGCCTT, which might look like this in most people, but turn into CTATCGCCTT in some people, replacing the second cytosine with a thymine.
The significance of a single nucleotide polymorphism can depend on the location and the specific nucleotide involved. Researchers estimate that there are about 10 million of them in the human genome, counting only polymorphisms that occur in at least 1% of the human population, making them statistically significant. Most appear in what is known as noncoding DNA, because it does not directly code for proteins. That doesn’t mean that single nucleotide polymorphisms don’t impact an individual genome, however, as they can affect the expression of other DNA if they’re in the wrong place.
When single nucleotide polymorphisms occur in the coding DNA, they can be classified as synonyms or substitutions. A single nucleotide polymorphism synonym does not change the protein produced using that DNA strand as a guideline, whereas substitution polymorphisms change the nature of the proteins produced. They can have a significant impact on genome expression, as the protein may be important. For example, a single nucleotide polymorphism may be linked to problems with the clotting factors used in the blood, in which case a patient’s blood may not clot properly after an injury.
One use for these distinctive variations is in genetic fingerprinting, in which a laboratory uses a genetic sample to determine whether two people are related or if someone was present at a crime scene. A single nucleotide polymorphism can be a very unique identifier that allows a laboratory to more closely confirm the accuracy of a match or mismatch. For example, technicians who compare blood found at a crime scene to a sample from a suspect might categorically rule out the suspect because the suspect may not have an SNP found in the blood at the scene.
Another use is in medical research. While a single nucleotide polymorphism doesn’t necessarily cause disease, it can increase a patient’s risk of developing disease and can change how the patient responds to medications. Pharmaceutical companies could theoretically tailor treatments for patients based on these genetic variations. Patients could also receive tests to highlight disease risks caused by single nucleotide polymorphisms, which could help them make prevention and screening decisions to catch disease early.
Protect your devices with Threat Protection by NordVPN
