en
Scientific article
English

Frequency of replication/transcription errors in (A)/(T) runs of human genes

Published inHuman genetics, vol. 109, no. 1, p. 40-47
Publication date2001
Abstract

To estimate the error rate of the gene expression machinery and its possible age-related increase, we compared the occurrence of polymerase errors during replication and transcription in (A)/(T) runs, in DNA and RNA of young and old individuals and of early- and late-passage cultured fibroblasts. We analyzed three human genes: TPRD, TGFBR2, and ATRX containing stretches of (A)8, (A)10, and (T)13, respectively. The error rate was determined by sequencing 100 cloned PCR or RT-PCR fragments from each DNA and RNA sample. The error rates in replication and transcription increased with the stretch length. The pooled error rates for genomic DNA were: TPRD (A)8, TGFBR2 (A)10, and ATRX (T)13: 1%+/-0.41, 15.8%+/-1.3, and 31.3%+/-2.9, while those for RNA were: 3.8%+/-0.5, 19.3%+/-2.1, and 54.3%+/-1.8, respectively. The deletions of one nucleotide were the most frequent errors. In the replication analysis, a significant difference was found in old versus young individuals for the ATRX (T)13. In the transcription analysis, significantly higher error rates were obtained in old versus young individuals for the TPRD (A)8 and TGFBR2 (A)10. For these genes, the error rate in RNA isolated from fibroblasts was significantly higher than that in blood. The data show a trend of age-related increase in replication/transcription errors; however further studies are necessary to confirm this hypothesis, since the sample size is small. This imperfect fidelity of the gene expression process may explain the evolutionary disadvantage of nucleotide repeats within coding sequences, and that these repeats are targets for mutations in human diseases.

Keywords
  • Adult
  • Aged
  • Aged, 80 and over
  • Aging/ genetics
  • Base Sequence
  • Cell Line
  • DNA/genetics
  • DNA Damage
  • DNA Helicases
  • DNA Primers/genetics
  • DNA Replication/ genetics
  • DNA-Binding Proteins/genetics
  • Female
  • Genome, Human
  • Humans
  • Mutation
  • Nuclear Proteins
  • Protein-Serine-Threonine Kinases
  • Proteins/genetics
  • RNA/genetics
  • Receptors, Transforming Growth Factor beta/genetics
  • Repetitive Sequences, Nucleic Acid
  • Transcription Factors/genetics
  • Transcription, Genetic
Citation (ISO format)
GIACOBINO, Ariane et al. Frequency of replication/transcription errors in (A)/(T) runs of human genes. In: Human genetics, 2001, vol. 109, n° 1, p. 40–47.
Main files (1)
Article
accessLevelRestricted
Identifiers
ISSN of the journal0340-6717
477views
0downloads

Technical informations

Creation07/12/2010 11:59:29 AM
First validation07/12/2010 11:59:29 AM
Update time03/14/2023 3:52:22 PM
Status update03/14/2023 3:52:22 PM
Last indexation02/12/2024 6:55:37 PM
All rights reserved by Archive ouverte UNIGE and the University of GenevaunigeBlack