recombinant DNA

DNA deoxyribonucleic acid.

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complementary DNA  (cDNA), copy DNA DNA transcribed from a specific RNA through the action of the enzyme reverse transcriptase.

mitochondrial DNA  (mtDNA) the DNA of the mitochondrial chromosome, existing in several thousand copies per cell and inherited exclusively from the mother.

nuclear DNA  (nDNA) the DNA of the chromosomes found in the nucleus of a eukaryotic cell.

recombinant DNA  DNA artificially constructed by insertion of foreign DNA into the DNA of an appropriate organism so that the foreign DNA is replicated along with the host DNA.

repetitive DNA  nucleotide sequences occurring multiply within a genome; it is characteristic of eukaryotes and some is satellite DNA while other sequences encode genes for ribosomal RNA and histones.

satellite DNA  short, highly repeated eukaryotic DNA sequences, usually clustered in heterochromatin and generally not transcribed.

single copy DNA  (scDNA) nucleotide sequences present once in the haploid genome, as are most of those encoding polypeptides in the eukaryotic genome.

spacer DNA  the nucleotide sequences occurring between genes.

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recombinant DNA

n.

Genetically engineered DNA prepared by transplanting or splicing one or more segments of DNA into the chromosomes of an organism from a different species. Such DNA becomes part of the host's genetic makeup and is replicated.

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recombinant DNA,

a DNA molecule in which rearrangement of the genes has been experimentally induced. Enzymes are used to break isolated DNA molecules into fragments that are then rearranged in the desired sequence. DNA sequences from another organism of the same or a different species may also be introduced into the molecule, which is then replicated, resulting in both genotypic and phenotypic alterations in the organism that carries the recombinant DNA. See also genetic engineering.