Threose nucleic acid

Threose nucleic acid (TNA) is a polymer similar to DNA or RNA but differing in the composition of its "backbone". TNA is not known to occur naturally.

DNA and RNA have a deoxyribose and ribose sugar backbone, respectively, whereas TNA's backbone is composed of repeating threose units linked by phosphodiester bonds. The threose molecule is easier to assemble than ribose making it a possible precursor to RNA.

DNA-TNA hybrid chains have been made in the laboratory using DNA polymerase.

TNA can specifically base pair with RNA and DNA; this capability and chemical simplicity suggests that TNA could have preceded RNA as genetic material.

See also

• Abiogenesis
• Glycol nucleic acid
• Peptide nucleic acid

External links

• "Was simple TNA the first nucleic acid on Earth to carry a genetic code?", New Scientist

  ORIGIN OF LIFE: A Simpler Nucleic Acid", Leslie Orgel

References

fr:Acide nucléique à thréose