Single Nucleotide Polymorphism (SNP)

Definition

A single nucleotide polymorphism (SNP) is a variation at a single position in a DNA sequence among individuals, where a nucleotide in the genome is replaced with another nucleotide. These variations can influence how genes function and are associated with different traits or diseases. SNPs serve as important genetic markers in various applications, such as determining genetic diversity, studying population genetics, and conducting genome-wide association studies (GWAS).

5 Must Know Facts For Your Next Test

1. SNPs are the most common type of genetic variation in humans, with millions of SNPs identified across the human genome.
2. Each SNP represents a difference in a single DNA base pair, such as adenine (A) being replaced by guanine (G).
3. SNPs can be categorized into two types: synonymous (no change in amino acid) and non-synonymous (change in amino acid), influencing protein function.
4. In genome-wide association studies (GWAS), SNPs are used to identify genetic variants associated with diseases by comparing SNP patterns between affected and unaffected individuals.
5. The analysis of SNPs can help in understanding complex traits, susceptibility to diseases, and responses to drugs, making them crucial in personalized medicine.

Review Questions

• How do single nucleotide polymorphisms (SNPs) contribute to genetic diversity within populations?
  • Single nucleotide polymorphisms contribute to genetic diversity by introducing variations at specific positions in the DNA sequence among individuals. These variations can lead to differences in traits or responses to environmental factors, allowing populations to adapt over time. The accumulation of SNPs across the genome provides a rich resource for studying evolutionary relationships and genetic variation within and between populations.
• Discuss the role of SNPs in genome-wide association studies (GWAS) and their significance in identifying disease-related genes.
  • SNPs play a pivotal role in genome-wide association studies (GWAS) as they serve as markers for identifying genetic variations associated with diseases. By comparing the frequency of SNPs between individuals with a particular disease and those without, researchers can pinpoint regions of the genome that may harbor disease-related genes. This helps in unraveling the genetic basis of complex traits and diseases, paving the way for potential therapeutic targets and personalized treatment approaches.
• Evaluate the impact of SNP analysis on personalized medicine and how it shapes individual treatment plans based on genetic profiles.
  • SNP analysis has significantly impacted personalized medicine by enabling tailored treatment plans based on an individual's unique genetic makeup. By understanding how specific SNPs influence drug metabolism, efficacy, and side effects, healthcare providers can customize therapies to optimize patient outcomes. This approach not only enhances treatment effectiveness but also reduces the risk of adverse reactions, highlighting the importance of integrating SNP data into clinical practice for improved healthcare solutions.

Related terms

Genotype: The genetic constitution of an individual organism, specifically referring to the alleles present at a particular locus on their chromosomes.

Allele: One of two or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome.

Linkage Disequilibrium: The non-random association of alleles at different loci in a given population, often used to study the relationship between SNPs and traits or diseases.