single nucleotide polymorphism

Thân thiện

A scientist examines a single nucleotide polymorphism on a computer screen.

Definition

Noun: A single nucleotide polymorphism (SNP) is a common type of genetic variation. It occurs when a single building block of DNA (a nucleotide) at a specific position in the genome differs between members of a species or between paired chromosomes in an individual. These variations are stable, must be present in a significant portion of the population (typically >1%), and are a primary source of genetic diversity.

Usage

SNPs are a fundamental concept in genetics and genomics. * They are used as biological markers to locate genes associated with diseases. * Scientists study SNPs to understand how individuals respond to pathogens, chemicals, drugs, and vaccines. * The phrase is often used in its abbreviated form, "SNP" (pronounced "snip").

Examples

• Researchers identified a single nucleotide polymorphism linked to an increased risk for the disease.
• The study cataloged millions of single nucleotide polymorphisms across the human genome.
• This SNP causes a change from an adenine (A) to a guanine (G) at a specific locus.

Advanced Usage

• "SNP genotyping": The process of determining which genetic variant (allele) an individual possesses for a specific SNP.
• "SNP array": A type of DNA microarray used to detect polymorphisms at hundreds of thousands of specific SNP locations simultaneously.
• "Tag SNP": A representative SNP in a region of the genome with high linkage disequilibrium, allowing it to identify a set of associated SNPs without testing every one.

Variants and Related Words

• Polymorphism (n): The general occurrence of two or more clearly different forms or variants in a population. A single nucleotide polymorphism is one specific category of polymorphism.
• Variant (n): A general term for a difference in DNA sequence. All SNPs are variants, but not all variants are SNPs (e.g., insertions or deletions are not SNPs).
• Mutation (n): A broader term for any change in the DNA sequence. A SNP can be considered a type of point mutation that has become common in a population.

Synonyms

• Point mutation (when referring to the specific change at the nucleotide level, though this term does not imply commonality in a population).
• Genetic marker (a general term for a gene or DNA sequence with a known location; many SNPs are used as genetic markers).

Related Phrases

• "To be associated with": SNPs are frequently described as being a trait, disease risk, or drug response.
  • The SNP was strongly associated with metabolizing the medication slowly.
• "To map a SNP": To determine the specific chromosomal location of a polymorphism.
  • The team's goal was to map the SNP to a precise region on chromosome 17.

Học thuật

Noun

1. (genetics) genetic variation in a DNA sequence that occurs when a single nucleotide in a genome is altered; SNPs are usually considered to be point mutations that have been evolutionarily successful enough to recur in a significant proportion of the population of a species

Từ đồng nghĩa

• snp