Single nucleotide polymorphism (SNP)

Definition

A single nucleotide polymorphism (SNP) is a variation at a single position in a DNA sequence among individuals. SNPs are the most common type of genetic variation and can occur in coding regions, regulatory regions, or non-coding regions of the genome, playing a critical role in gene structure and function, and influencing traits and diseases.

5 Must Know Facts For Your Next Test

1. SNPs are estimated to occur once every 300 nucleotides in the human genome, leading to millions of SNPs across individuals.
2. Most SNPs have no effect on health or development, but some can influence how individuals respond to drugs, susceptibility to diseases, and other traits.
3. SNPs can be categorized into two types: synonymous (do not change the amino acid sequence) and nonsynonymous (alter the amino acid sequence), which may affect protein function.
4. Many genome-wide association studies (GWAS) utilize SNPs to identify genetic variants associated with diseases or traits by comparing SNP patterns between affected and unaffected individuals.
5. SNPs are also important in personalized medicine, as they can help tailor treatments based on an individual's unique genetic makeup.

Review Questions

• How do single nucleotide polymorphisms (SNPs) contribute to genetic diversity among individuals?
  • Single nucleotide polymorphisms (SNPs) contribute to genetic diversity by introducing variations at specific positions in the DNA sequence. These variations can lead to differences in phenotypes among individuals, such as variations in physical traits, susceptibility to diseases, and responses to medications. As SNPs are common throughout the genome, they serve as a rich source of information for understanding how genetic differences influence individual characteristics.
• Discuss the role of SNPs in genome-wide association studies (GWAS) and their importance in understanding complex traits.
  • In genome-wide association studies (GWAS), SNPs serve as key markers for identifying genetic variations associated with complex traits and diseases. Researchers compare the frequency of specific SNPs in populations with and without a particular trait to find associations. This approach helps pinpoint genetic risk factors for conditions like diabetes or heart disease, enhancing our understanding of the underlying biological mechanisms and paving the way for potential therapeutic interventions.
• Evaluate how SNPs can impact personalized medicine and the future of healthcare.
  • SNPs have significant implications for personalized medicine by enabling healthcare providers to tailor treatments based on an individual's unique genetic profile. For instance, understanding which SNPs affect drug metabolism can help predict patient responses to medications, minimizing adverse effects and optimizing efficacy. As research continues to uncover the relationships between SNPs and various health conditions, the integration of genomic data into clinical practice is poised to revolutionize healthcare by promoting more effective and individualized treatment strategies.

Related terms

Genotype: The genetic constitution of an individual organism, often represented by the alleles present at specific loci.

Allele: One of the different forms of a gene that can exist at a single locus on a chromosome.

Haplotype: A group of genes or genetic markers that are inherited together from a single parent, often used in studying SNP associations.