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A point mutation in which a purine is replaced by a pyrimidine, or a pyrimidine is replaced by a purine.

[Probably trans- + (in)version.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


1. a turning across, or into, something else
2. (Microbiology) (in nucleic acid) the substitution of a purine for a pyrimidine, or vice versa, by mutation
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
References in periodicals archive ?
The D108V mutation involves a conservative A>T transversion at position 323 of exon 4.
Totally, 99-nucleotide base substitutions were observed with seven variables, which accounted for six transitions and one transversion. Four single nucleotide polymorphismswereobserved in our study.
Sequence analysis of these PCR products showed a new A-T synonymous transversion mutation (Table) at pagA position bp 981, where the start ATG = bp 1, 2, 3, or position 2784 by using the coordinates described by Price et al.
To examine the stability of our hypothesis under weighted parsimony, we added transversion and amino acid characters to our matrix.
To acknowledge above data, we screen GJA8 gene of 27 cataract patients with no family history of cataract, a subtle 1104G>C (pE368Q) (GenBank KY556641) transversion that substitutes glutamic acid to glutamine was identified at exon 2 of GJA8 gene in one of the patient, which revealed that glutamic acid at position 368 in normal GJA8 protein was changed to glutamine, which is highlighted in Figure 6.
* T/A transversion at position -1398 (from the start of transcription), which is in complete allelic association with the G/A transition at position -1396 (T-1398A, G-1396A) (13)
(1994) use fixed transition/ transversion rate ratios (that is, [Kappa] = 4 for gophers and [Kappa] = 10 for lice, whereas our maximum-likelihood estimates of [Kappa] from the data are about 4.4 and 4.1 for the gopher and louse sequences, respectively).
number of transition and transversion substitutions for all pairwise comparisons among taxa for each codon position in DAMBE.
The phylogenetic analysis was performed on a 572-bp region of the amplicons by using a weighted maximum parsimony method, transversion:transition weighting of 5:1, and Phylogenetic Analysis Using Parsimony (PAUP) software version 4.0b4a for Macintosh (3).
We found two novel mutations in the EDN3 gene: a missense mutation (E48D) in exon 2 resulting from a G>C transversion; and a de novo C>A transversion at nucleotide -19 from the start codon (5'UT -19C>A), which could be affecting as yet unexplored regulatory regions.
From the above results, we also suggest that a transition of G to A at nucleotide 211 in exon 1 of the UGT1A1 gene would form the ht2 haplotype, whereas a transversion of T to G at nucleotide -3279 in the promoter region of the UGT1A1 gene would form the ht3 haplotype.