Poly(T) variation in heteroderid nematode mitochondrial genomes is predominantly an artefact of amplification.
J Mol Evol
; 72(2): 182-92, 2011 Feb.
Article
em En
| MEDLINE
| ID: mdl-21161202
ABSTRACT
We assessed the rate of in vitro polymerase errors at polythymidine [poly(T)] tracts in the mitochondrial DNA (mtDNA) of a heteroderid nematode (Heterodera cajani). The mtDNA of these nematodes contain unusually high numbers of poly(T) tracts, and have previously been suggested to contain biological poly(T) length variation. However, using a cloned molecule, we observed that poly(T) variation was generated in vitro at regions containing more than six consecutive Ts. This artefactual error rate was estimated at 7.3 × 10(-5) indels/poly(T) tract >6 Ts/cycle. This rate was then compared to the rate of poly(T) variation detected after the amplification of a biological sample, in order to estimate the 'biological + artefactual' rate of poly(T) variation. There was no significant difference between the artefactual and the artefactual + biological rates, suggesting that the majority of poly(T) variation in the biological sample was artefactual. We then examined the generation of poly(T) variation in a range of templates with tracts up to 16 Ts long, utilizing a range of Heteroderidae species. We observed that T deletions occurred five times more frequently than insertions, and a trend towards increasing error rates with increasing poly(T) tract length. These findings have significant implications for studies involving genomes with many homopolymer tracts.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Poli T
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Tylenchoidea
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Variação Genética
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Artefatos
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Técnicas de Amplificação de Ácido Nucleico
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Genoma Helmíntico
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Genoma Mitocondrial
Limite:
Animals
Idioma:
En
Revista:
J Mol Evol
Ano de publicação:
2011
Tipo de documento:
Article
País de afiliação:
Austrália