Synthetic DNA Expands the Genetic Alphabet - Summary - MDSpire
Coming Soon: Introducing MDSpire News. Learn more
Conexiant’s news site is now MDSpire News. Learn more

Synthetic DNA Expands the Genetic Alphabet

Researchers identify the structural basis of eight-letter genetic transcription

  • September 29, 2026

  • 4 min

Share

Objective:

To investigate the ability of Escherichia coli RNA polymerase to transcribe an expanded genetic alphabet containing eight nucleotide letters.

Approach:
  • Study Design: The researchers created DNA and RNA templates with synthetic bases and tested the incorporation of these bases by E. coli RNA polymerase.
  • Error Reduction: A modified base called Z* was tested to reduce incorrect pairing with guanine.
  • Structural Analysis: Cryo-electron microscopy was used to produce structures of RNA polymerase interacting with synthetic bases.
Key Findings:
  • E. coli RNA polymerase can efficiently incorporate synthetic nucleotides P, Z, B, and S.
  • The incorporation rate of the synthetic pair P:Z is approximately twofold lower than that of natural guanine-cytosine.
  • The modified base Z* significantly reduces incorrect pairing with guanine while maintaining pairing with P.
  • Cryo-electron microscopy revealed that synthetic pairs fit into the enzyme's active site similarly to natural base pairs.
Interpretation:

The study enhances understanding of how biological machinery interacts with synthetic genetic material.

Limitations:
  • The study was conducted in a cell-free system and did not demonstrate transcription in living bacteria.
  • Single-nucleotide experiments may overestimate error rates due to lack of competition from correct matching nucleotides.
Conclusion:

Further research is needed to assess the functionality of the expanded genetic alphabet in living cells.

Sources:

Original Source(s)

Synthetic DNA Expands the Genetic Alphabet

  • September 29, 2026

Related Content

FDA clears targeted cholangiocarcinoma therapy

In the single-arm REFOCUS trial, 46% of patients responded to treatment, with a median response duration of 11.8 months.

ECP 2026: Combined Approach Predicts Metastasis in Prostate Cancer

Integrating spatial transcriptomics and machine learning may predict lymph node metastasis in treatment-naive prostate cancer

  • September 17, 2026

  • 3 min
FDA approves combo for ESR1-mutated breast cancer

In an exploratory subgroup analysis of patients with ESR1-mutated tumors, median progression-free survival was 11.1 months with the combination and 5.5 months with imlunestrant alone.