How does single-nucleotide polymorphism (SNP) work?

A DNA sequence is composed of a chain made up of 4 nucleotide bases: A, C, G, and T. A single-nucleotide polymorphism may replace the nucleotide thymine (T) with the nucleotide (C) in a certain stretch of DNA. These variations can happen throughout the genome and can impact traits or disease susceptibility. SNPs are most commonly found in the DNA between genes and act as biological markers, aiding in identifying disease-associated genes. 

Single-nucleotide polymorphisms are widely studied to understand genetic diversity, disease risk, and individual differences in response to drugs or environmental factors. They serve as valuable genetic markers and are detected through various techniques like DNA sequencing or genotyping arrays. They are also useful for tracking disease-associated genetic variants within families.