base pair

American  

noun

Genetics.

1. any of the pairs of the hydrogen-bonded purine and pyrimidine bases that form the links between the sugar-phosphate backbones of nucleic acid molecules: the pairs are adenine and thymine in DNA, adenine and uracil in RNA, and guanine and cytosine in both DNA and RNA.

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base pair Scientific  

1. Any of the pairs of nucleotides connecting the complementary strands of a molecule of DNA or RNA and consisting of a purine linked to a pyrimidine by hydrogen bonds. The base pairs are adenine-thymine and guanine-cytosine in DNA, and adenine-uracil and guanine-cytosine in RNA or in hybrid DNA-RNA pairing. Base pairs may be thought of as the rungs of the DNA ladder.

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Etymology

Origin of base pair

First recorded in 1960–65

Example Sentences

Nearly all modern humans carry a version of the NOVA1 gene that differs by a single DNA base pair from the version found in Neanderthals.

From Science Daily • Oct. 16, 2025

His lab manipulated DNA molecules to make the tiny motor's turbine, which consisted of 30 double-stranded DNA helices engineered into an axle and three blades of about 72 base pair length.

From Science Daily • Jan. 19, 2024

Such an altered base pair, known as a tautomer, can quickly jump back to its original arrangement.

From Scientific American • Sep. 21, 2022

If the rate of replication in a particular prokaryote is 900 nucleotides per second, how long would it take to make two copies of a 1.2 million base pair genome?

From Textbooks • Jun. 9, 2022

Gene, protein, function, and fate were strung in a chain: one chemical alteration in one base pair in DNA was sufficient to “encode” a radical change in human fate.

From "The Gene" by Siddhartha Mukherjee