Transversion: Difference between revisions

Latest revision as of 16:26, 16 February 2025

Transversion[edit]

A transversion is a type of point mutation in DNA where a purine is substituted for a pyrimidine, or vice versa. This contrasts with a transition, where a purine is replaced with another purine, or a pyrimidine is replaced with another pyrimidine.

Types of Transversions[edit]

Transversions can be categorized based on the specific bases involved:

Purine to Pyrimidine:

 * Adenine (A) to Cytosine (C) or Thymine (T)
 * Guanine (G) to Cytosine (C) or Thymine (T)

Pyrimidine to Purine:

 * Cytosine (C) to Adenine (A) or Guanine (G)
 * Thymine (T) to Adenine (A) or Guanine (G)

Biological Significance[edit]

Transversions are less common than transitions but can have significant effects on the genetic code. Because they involve a change in the chemical structure of the base, transversions can lead to more drastic changes in the amino acid sequence of proteins, potentially altering protein function.

Mutational Effects[edit]

Transversions can result in:

Missense mutations, where the change in base leads to the incorporation of a different amino acid in the protein.
Nonsense mutations, where the change creates a premature stop codon, leading to truncated proteins.
Silent mutations, where the change does not affect the amino acid sequence due to the redundancy of the genetic code.

Detection and Analysis[edit]

Transversions can be detected through various molecular biology techniques, such as DNA sequencing and polymerase chain reaction (PCR). Understanding the frequency and distribution of transversions in a genome can provide insights into the mechanisms of mutagenesis and the evolutionary pressures acting on an organism.

Related Pages[edit]

@@ Line 1: / Line 1: @@
 == Transversion ==
-A '''transversion''' is a type of [[nucleotide]] substitution in [[genetics]] where a [[purine]] is replaced with a [[pyrimidine]], or vice versa. This contrasts with a [[transition (genetics)|transition]], where a purine is replaced with another purine, or a pyrimidine is replaced with another pyrimidine.
+[[File:All_transitions_and_transversions.svg|thumb|right|Diagram showing all possible transitions and transversions in DNA.]]
-== Types of Transversions ==
+A '''transversion''' is a type of [[point mutation]] in [[DNA]] where a [[purine]] is substituted for a [[pyrimidine]], or vice versa. This contrasts with a [[transition (genetics)|transition]], where a purine is replaced with another purine, or a pyrimidine is replaced with another pyrimidine.
-Transversions can be categorized into four types based on the specific bases involved:
+=== Types of Transversions ===
-* Adenine (A) to Cytosine (C)
+Transversions can be categorized based on the specific bases involved:
-* Adenine (A) to Thymine (T)
-* Guanine (G) to Cytosine (C)
-* Guanine (G) to Thymine (T)
-Similarly, the reverse changes (C to A, T to A, C to G, T to G) are also considered transversions.
+* '''Purine to Pyrimidine:'''
+  * [[Adenine]] (A) to [[Cytosine]] (C) or [[Thymine]] (T)
+  * [[Guanine]] (G) to Cytosine (C) or Thymine (T)
+* '''Pyrimidine to Purine:'''
+  * Cytosine (C) to Adenine (A) or Guanine (G)
+  * Thymine (T) to Adenine (A) or Guanine (G)
-== Biological Significance ==
+=== Biological Significance ===
-Transversions are less common than transitions in the [[genome]] due to the structural differences between purines and pyrimidines, which make such substitutions more disruptive to the [[DNA]] double helix. However, they can have significant effects on [[gene expression]] and [[protein]] function, potentially leading to [[genetic disorders]] or [[cancer]].
+Transversions are less common than transitions but can have significant effects on the [[genetic code]]. Because they involve a change in the chemical structure of the base, transversions can lead to more drastic changes in the [[amino acid]] sequence of proteins, potentially altering protein function.
-== Detection and Analysis ==
+=== Mutational Effects ===
-Transversions can be detected through various [[molecular biology]] techniques, such as [[DNA sequencing]]. They are often analyzed in the context of [[evolutionary biology]] to understand the [[mutation rate]] and [[phylogenetic]] relationships among species.
+Transversions can result in:
-== Related Pages ==
+* '''[[Missense mutation|Missense mutations]]''', where the change in base leads to the incorporation of a different amino acid in the protein.
+* '''[[Nonsense mutation|Nonsense mutations]]''', where the change creates a premature [[stop codon]], leading to truncated proteins.
+* '''[[Silent mutation|Silent mutations]]''', where the change does not affect the amino acid sequence due to the redundancy of the genetic code.
-* [[Transition (genetics)]]
+=== Detection and Analysis ===
-* [[Mutation]]
-* [[DNA]]
-* [[Genetics]]
-== References ==
+Transversions can be detected through various [[molecular biology]] techniques, such as [[DNA sequencing]] and [[polymerase chain reaction]] (PCR). Understanding the frequency and distribution of transversions in a genome can provide insights into the mechanisms of [[mutagenesis]] and the evolutionary pressures acting on an organism.
-{{Reflist}}
+== Related Pages ==
-== External Links ==
+* [[Transition (genetics)]]
+* [[Point mutation]]
-* [https://en.wikipedia.org/wiki/Transversion Transversion on Wikipedia]
+* [[DNA replication]]
+* [[Genetic code]]
-[[File:All_transitions_and_transversions.svg|thumb|right|Diagram showing all possible transitions and transversions.]]
+{{Genetics}}
 [[Category:Genetics]]
 [[Category:Molecular biology]]