gene amplification

n. A cellular process characterized by the production of multiple copies of a particular gene or genes to amplify the phenotype that the gene confers on the cell. Drug resistance in cancer cells is linked to amplification of the gene that prevents absorption of the chemotherapeutic agent by the cell.

gene′ amplifica`tion

n. 1. an increase in the frequency of replication of a DNA segment. 2. such an increase induced by a polymerase chain reaction. [1970–75]

Translations

gene amplification

Gene amplification

The process by which a cell specifically increases the copy number of a particular gene to a greater extent than it increases the copy number of genes composing the remainder of the genome (all the genes which make up the genetic machinery of an organism). It is therefore distinguished from duplication, which is a precise doubling of the genome preparatory to cell division, and endoreduplication, which leads to endopolyploidy.

Gene amplification results from the repeated replication of the deoxyribonucleic acid (DNA) in a limited portion of the genome, in the absence of or to a much greater extent than replication of DNA composing the remainder of the genome. Thus is formed a cell in which the genes composing a limited portion of the genome are present in relatively high copy number, while the genes composing the remainder of the genome are present in approximately normal copy number. See Deoxyribonucleic acid (DNA)

Since gene amplification increases the copy number of a specific region of the genome without altering the copy number of genes composing the remainder of the genome, it would appear to offer an alternative method for developmental control of gene expression. By increasing the number of copies of a particular gene, the number of gene copies available for transcription could thereby be increased.

In a number of instances of gene amplification, the amplification phenomenon appears to be developmentally regulated, and the amplified copies of the gene are subsequently lost from the cell. Studies on cells in culture have demonstrated “amplification” of genes involved in resistance to specific drugs. See Gene, Gene action

gene amplification

[′jēn ‚am·plə·fə‚kā·shən] (cell and molecular biology) Any process by which a deoxyribonucleic acid sequence is disproportionately duplicated in comparison with the parent genome. (genetics) Repeated replication in a single cell cycle of the deoxyribonucleic acid (DNA) in a limited portion of the genome, resulting in an increase in the number of copies of a particular gene or DNA segment.

gene amplification

amplification

[am″plĭ-fĭ-ka´shun] the process of making larger, such as the increase of an auditory or visual stimulus, as a means of improving its perception.DNA amplification artificial increase in the number of copies of a particular DNA fragment into millions of copies through replication of the segment into which it has been cloned, a type of amplification" >nucleic acid amplification.gene amplification a process by which the number of copies of a gene is increased in certain cells because extra copies of DNA are made in response to certain signals of cell development or of stress from the environment. In humans this process is seen most often in malignant cells.nucleic acid amplification amplification of a specific nucleic acid sequence, such as to test for presence of a given virus or bacteria in a sample. Types include amplification" >DNA amplification, ligase chain reaction, and polymerase chain reaction.

gene amplification

Genetics A process by which specific DNA sequences are replicated disproportionately greater than their representation in the parent source; GS of cellular oncogenes occurs in malignancy, where the copy number is a crude benchmark of tumor aggressiveness. See PCR.

gene amplification

a process in which many copies are made of some genes at one time, while other genes are not replicated. The replicated genes enable enhanced manufacture of product in a short time. For example, rRNA genes are amplified about 4,000 times in oocytes of the clawed toad Xenopus laevis to assist in protein production during egg development. The POLYMERASE CHAIN REACTION can be used for gene amplification in vitro.

单词	gene amplification
释义	gene amplification gene amplification n. A cellular process characterized by the production of multiple copies of a particular gene or genes to amplify the phenotype that the gene confers on the cell. Drug resistance in cancer cells is linked to amplification of the gene that prevents absorption of the chemotherapeutic agent by the cell. gene′ amplifica`tion n. 1. an increase in the frequency of replication of a DNA segment. 2. such an increase induced by a polymerase chain reaction. [1970–75] Translations gene amplification Gene amplification The process by which a cell specifically increases the copy number of a particular gene to a greater extent than it increases the copy number of genes composing the remainder of the genome (all the genes which make up the genetic machinery of an organism). It is therefore distinguished from duplication, which is a precise doubling of the genome preparatory to cell division, and endoreduplication, which leads to endopolyploidy. Gene amplification results from the repeated replication of the deoxyribonucleic acid (DNA) in a limited portion of the genome, in the absence of or to a much greater extent than replication of DNA composing the remainder of the genome. Thus is formed a cell in which the genes composing a limited portion of the genome are present in relatively high copy number, while the genes composing the remainder of the genome are present in approximately normal copy number. See Deoxyribonucleic acid (DNA) Since gene amplification increases the copy number of a specific region of the genome without altering the copy number of genes composing the remainder of the genome, it would appear to offer an alternative method for developmental control of gene expression. By increasing the number of copies of a particular gene, the number of gene copies available for transcription could thereby be increased. In a number of instances of gene amplification, the amplification phenomenon appears to be developmentally regulated, and the amplified copies of the gene are subsequently lost from the cell. Studies on cells in culture have demonstrated “amplification” of genes involved in resistance to specific drugs. See Gene, Gene action gene amplification [′jēn ‚am·plə·fə‚kā·shən] (cell and molecular biology) Any process by which a deoxyribonucleic acid sequence is disproportionately duplicated in comparison with the parent genome. (genetics) Repeated replication in a single cell cycle of the deoxyribonucleic acid (DNA) in a limited portion of the genome, resulting in an increase in the number of copies of a particular gene or DNA segment. gene amplification amplification [am″plĭ-fĭ-ka´shun] the process of making larger, such as the increase of an auditory or visual stimulus, as a means of improving its perception.DNA amplification artificial increase in the number of copies of a particular DNA fragment into millions of copies through replication of the segment into which it has been cloned, a type of amplification" >nucleic acid amplification.gene amplification a process by which the number of copies of a gene is increased in certain cells because extra copies of DNA are made in response to certain signals of cell development or of stress from the environment. In humans this process is seen most often in malignant cells.nucleic acid amplification amplification of a specific nucleic acid sequence, such as to test for presence of a given virus or bacteria in a sample. Types include amplification" >DNA amplification, ligase chain reaction, and polymerase chain reaction. gene amplification n. A cellular process characterized by the production of multiple copies of a particular gene or genes to amplify the phenotype that the gene confers on the cell. Drug resistance in cancer cells is linked to amplification of the gene that prevents absorption of the chemotherapeutic agent by the cell. gene amplification Genetics A process by which specific DNA sequences are replicated disproportionately greater than their representation in the parent source; GS of cellular oncogenes occurs in malignancy, where the copy number is a crude benchmark of tumor aggressiveness. See PCR. gene amplification a process in which many copies are made of some genes at one time, while other genes are not replicated. The replicated genes enable enhanced manufacture of product in a short time. For example, rRNA genes are amplified about 4,000 times in oocytes of the clawed toad Xenopus laevis to assist in protein production during egg development. The POLYMERASE CHAIN REACTION can be used for gene amplification in vitro. ThesaurusSeeamplification
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