DNA's base sequence stores biological information.
Key knowledge
DNA is a nucleic acid whose sequence of bases carries genetic information. In the usual double helix, sugar-phosphate backbones support bases paired A with T and C with G. DNA sequence can specify protein or functional RNA products.
Conditions and scope
Describes ordinary cellular DNA and its usual double-stranded structure.
Sequence information contributes to biological function together with regulation and environmental context.
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References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
NHGRI's molecular definition, base pairing and information scope; no DNA sequencing was performed.
2026-10-10 · English structure and protein/RNA distinction checked against the NHGRI DNA glossary entry; deterministic claims about traits are excluded.
Foundational review
2026-10-10 · Fresh primary-source inspection of the complete compact record, including every statement, equation, quantity and material condition, followed by independent AI editorial review. This check does not certify all linked lessons or every passage of every cited publication.
Sources from other places
Agreement within this scope
DNA sequence, complementary pairing and sugar-phosphate backbones.
DNA is a nucleic acid whose sequence of bases carries genetic information. In the usual double helix, sugar-phosphate backbones support bases paired A with T and C with G. DNA sequence can specify protein or functional RNA products.
Gene expression is the use of a gene's information to produce a functional product. Transcription produces RNA; for protein-coding genes, messenger RNA is translated into an amino-acid sequence. Some genes produce functional RNA that is not translated into protein.
Cellular expression uses genetic sequence information to produce RNA or protein.
In semiconservative replication of double-stranded DNA, each parental strand serves as a template for a new complementary strand. Each resulting double helix contains one parental strand and one newly synthesized strand.
DNA is a nucleic acid whose sequence of bases carries genetic information. In the usual double helix, sugar-phosphate backbones support bases paired A with T and C with G. DNA sequence can specify protein or functional RNA products.
Complementary DNA strands serve as templates in semiconservative copying.
Base-excision repair begins when a glycosylase removes a recognized damaged base, leaving a site that is processed and restored by DNA synthesis and ligation. Nucleotide-excision repair instead removes a DNA segment containing a recognized lesion. Both use the complementary strand as an informational template when that template remains available.
Complementarity provides an intact repair template.
Replicative DNA polymerases extend a primer's 3′ end while copying a template, synthesizing DNA 5′→3′. Helicase opens the duplex, primase supplies primers, topoisomerases relieve torsional stress and ligase joins processed fragments. Opposite template orientations require continuous leading-strand and discontinuous lagging-strand synthesis at a typical fork.
A nucleotide contains a base, a pentose sugar and one or more phosphate groups. DNA uses deoxyribose, with hydrogen at sugar carbon 2′; RNA uses ribose, with a 2′ hydroxyl. Their usual bases are A, G and C with T in DNA and U in RNA. In ordinary DNA/RNA chains, 3′–5′ phosphodiester linkages connect sugars through phosphate, giving backbone directionality. The two strands of the usual DNA double helix are antiparallel; RNA can also fold by internal base pairing.
DNA base sequence is carried on a directional covalent sugar–phosphate backbone distinct from interstrand pairing.