Types of dna mutations
Pro Research Analysisby 
Searched over 200M research papers
Types of DNA Mutations
DNA mutations are alterations in the genetic material that can have significant implications for an organism's health and development. These mutations can be classified into several types based on their nature and the mechanisms by which they occur.
Single-Nucleotide Polymorphisms (SNPs)
Single-nucleotide polymorphisms (SNPs) are the most common type of DNA mutation. They involve a change of a single base pair in the DNA sequence. SNPs can be challenging to detect due to the minimal difference between the mutant and wild-type DNA. Advanced techniques using gold nanoparticles and MutS enzymes have been developed to achieve highly sensitive detection of SNPs, which are crucial for diagnosing diseases such as cancer1.
Multi-Nucleotide Mutations (MNMs)
Multi-nucleotide mutations (MNMs) involve changes in multiple nucleotides within a short DNA segment. These mutations can occur simultaneously and are often found in close proximity to each other. Studies have shown that around 3% of human de novo single nucleotide variants (SNVs) are part of MNMs, with a significant number of these mutations occurring near recombination events and in late-replicating regions of the genome3.
Insertions and Deletions (Indels)
Insertions and deletions (indels) are mutations where nucleotides are added or removed from the DNA sequence. These mutations can vary in size from a single nucleotide to large segments of DNA. Indels can disrupt the reading frame of genes, leading to significant changes in protein function. The mutation rate for indels is lower than that for SNVs, but they still play a crucial role in genetic variation and disease3.
Structural Variants (SVs)
Structural variants (SVs) are large-scale mutations that involve substantial changes in the structure of the genome. These can include duplications, deletions, inversions, and translocations of large DNA segments. SVs are often influenced by the local DNA sequence environment and genomic architecture, which can predispose certain regions to higher mutation rates4.
Mitochondrial DNA Mutations
Mitochondrial DNA (mtDNA) mutations are changes that occur in the mitochondrial genome. These mutations can be somatic or inherited and are often observed in various types of cancer. The state of heteroplasmy, where both wild-type and mutant mtDNA coexist, can influence the phenotypic outcome of these mutations. The biological impact of mtDNA mutations depends on the proportion of mutant mtDNA within the cell5.
Clustered Mutations
Clustered mutations are non-random mutations that occur in close proximity within the genome. These clusters can arise from damaged long single-strand DNA regions, often formed at double-strand breaks and replication forks. Such mutations are frequently observed in yeast and human cancers, indicating a mechanism of hypermutation that contributes to rapid genetic variation7.
Mutational Signatures in Cancer
Mutational signatures are patterns of mutations that arise from specific mutational processes. In cancer genomes, multiple mutational processes generate characteristic signatures, including single base substitutions, doublet base substitutions, and small insertions and deletions. These signatures can be linked to various endogenous and exogenous factors, as well as defective DNA maintenance processes8 9.
Exonuclease Domain Mutations
Exonuclease domain mutations in DNA polymerase epsilon (POLE) lead to a high mutation frequency and specific mutation patterns. These mutations result in a mutator phenotype with a preference for certain nucleotide changes, such as C to A mutations. This type of mutation is associated with increased frequencies of recurrent nonsense mutations in key tumor suppressors and provides insights into the mechanisms of DNA replication and repair10.
Conclusion
Understanding the different types of DNA mutations is essential for comprehending their roles in genetic variation, disease development, and evolution. From single-nucleotide changes to large structural variants, each type of mutation contributes uniquely to the complexity of the genome and its functions. Advances in detection and characterization techniques continue to enhance our ability to study these mutations and their implications for human health.
Sources and full results
Most relevant research papers on this topic
Highly sensitive and selective detection of single-nucleotide polymorphisms using gold nanoparticle MutS enzymes and a micro cantilever resonator.
Our method for detecting and discriminating single-nucleotide polymorphisms (SNPs) using gold nanoparticles and a micro cantilever resonator is highly sensitive and selective, potentially aiding in cancer diagnosis.
Genetic and phenotypic characterization of dnaC mutations
The dnaC mutations in E. coli cause abrupt cessation of deoxyribonucleic acid synthesis at 42 C, suggesting a possible defect in chain elongation rather than initiation.
Multi-nucleotide de novo Mutations in Humans
Human DNA mutation rates are higher in late replicating regions and near recombination events, with 3% of de novo SNVs being part of multi-nucleotide mutations.
Highly CitedOn the sequence‐directed nature of human gene mutation: The role of genomic architecture and the local DNA sequence environment in mediating gene mutations underlying human inherited disease
Human gene mutations causing inherited diseases are shaped by the local DNA sequence environment and can be influenced indirectly by non-canonical secondary structures.
Highly CitedMitochondrial DNA mutations in human cancer
Somatic mitochondrial DNA mutations play a crucial role in human cancer development, with potential diagnostic and therapeutic implications.
Highly CitedNomenclature for the description of human sequence variations
The current nomenclature system for describing human sequence variations is largely accepted, but does not yet cover all types of mutations and more complex changes.
Highly CitedClustered mutations in yeast and in human cancers can arise from damaged long single-strand DNA regions.
Clustered mutations in yeast and human cancers are caused by simultaneous changes in randomly formed single-strand DNA, potentially contributing to rapid genetic variation.
Highly CitedThe repertoire of mutational signatures in human cancer
This study identifies 49 distinct mutational signatures in human cancer, revealing associations with DNA damage, repair, and replication mechanisms, but many signatures remain unidentified.
Rigorous JournalHighly CitedThe repertoire of mutational signatures in human cancer
This study identified 81 mutational signatures in human cancer, revealing associations to exogenous or endogenous exposures, defective DNA-maintenance processes, and unknown causes.
Rigorous JournalHighly CitedExonuclease mutations in DNA polymerase epsilon reveal replication strand specific mutation patterns and human origins of replication
POLE-exo* mutations in cancers lead to high mutation frequencies and strand-specific replication, providing a unique identifier for eukaryotic origins of replication.
In Vitro StudyHighly Cited