Glossary Term
DNA
A long linear double-stranded polymer formed from nucleotides attached to a deoxyribose backbone and found in the nucleus of a cell; associated with the transmission of genetic information.
Loading
Search products, companies, tests, and guides — go from query to quote request in one place.
Glossary Term
A long linear double-stranded polymer formed from nucleotides attached to a deoxyribose backbone and found in the nucleus of a cell; associated with the transmission of genetic information.
Glossary Term
Drug-, radiation-induced, or spontaneous injuries to DNA that introduce deviations from its normal double-helical conformation. These changes include structural distortions that interfere with replication and transcription, as well as point mutations that disrupt base pairs and exert damaging effects on future generations through changes in DNA sequence. If the damage is minor, it can often be repaired (DNA repair); extensive damage can induce apoptosis.
Glossary Term
A family of enzymes that catalyze the formation of phosphodiester bonds to repair broken strands of DNA.
Glossary Term
Enzymatic restoration of DNA structure after chemical, radiation, or spontaneous damage.
Glossary Term
A 50-150bp DNA sequence that increases the rate of transcription of coding sequences. It may be located at various distances and in either orientation upstream from, downstream from or within a structural gene. When bound by a specific transcription factor it increases the levels of expression of the gene, but is not sufficient alone to cause expression. Distinguished from a promoter, that is alone sufficient to cause expression of the gene when bound.
Glossary Term
Any DNA sequence rearrangement that results in the gain of one or more copies of a DNA segment that contains at least one gene.
Glossary Term
A deletion that results in the loss of a DNA segment encompassing an entire gene sequence.
Glossary Term
The complete genomic content of an organism, and possibly the full DNA sequence of that organism. It is contained in a set of chromosomes in eukaryotes, a single chromosome in bacteria, or a DNA or RNA molecule in viruses.
Glossary Term
The determination of the DNA sequence of an individual.
Glossary Term
Major protein component of chromatin. Highly conserved basic proteins, originally classified into classes based on the relative amounts of arginine and lysine in each protein. The various classes are now termed H1, H2A, H2B, H3, and H4. In chromatin, they are found in an octamer, containing two each of H2A, H2B, H3, and H4, complexed with DNA in nucleosomes. The histones in the octamer complex are also known as the core histones. The H1 class of histones, termed the linker histones, is loosely associated with the nucleosome.
Glossary Term
The process of exchange of genetic material between autonomous replicons, which depends on regions of extensive sequence homology between the participating DNA strands. This process involves double-strand breakage of one participant, resection of the break, and strand invasion, followed by formation, displacement and resolution of the Holliday junction. This process is involved in repairing broken DNA and creating combinations of genes that may be unique from the parent duplexes. Disruptions in this process can result in inviability, premature aging and predisposition to cancers and degenerative diseases.
Glossary Term
Non-coding, intervening sequences of DNA that are transcribed, but are removed from within the primary gene transcript and rapidly degraded during maturation of messenger RNA.