What is the definition of a single nucleotide polymorphism (SNP)?

A single nucleotide polymorphism (SNP) is defined as a variation at a single position in a DNA sequence among individuals. This means that, in a specific location of the genome, different individuals in a population may have different nucleotides (the building blocks of DNA) present. For example, in one individual, a particular base might be adenine (A), while in another individual, it could be guanine (G). SNPs are important because they can influence how individuals respond to diseases, environmental factors, and medications.

These variations are highly prevalent and can serve as important markers in genetic studies, helping researchers understand genetic diversity and associations with traits or diseases. SNPs can also play a role in the study of population genetics, evolution, and the mapping of genes related to specific conditions or physical traits.