4.Normal (historic wild type) cells vs. genetically engineered cells (those that have been engineered to cure a disease, resist an herbicide, etc.).

5.normal cells vs. those same cells treated with a given pharmaceutical (candidate).

Analysis generally involves measurement of gene expression markers (i.e., molecules synthesized, or cellular consequences such as apoptosis) to determine which genes are expressed (and when/how much, etc.). See

Galso GENE, GENE EXPRESSION, GENE EXPRESSION,, ( ),

PROFILING MICROARRAY TESTING GENOMICS FUNCTIONAL GENOMICS, EXPRESS, EXPRESSED SEQUENCE TAGS (EST), ZINC FINGER PROTEINS,

BIOCHIPS, HIGH-THROUGHPUT SCREENING (HTS),

MICROFLUIDICS, HERBICIDE-TOLERANT CROP,

GENE DELIVERY (GENE THERAPY), HORMONE,

PROTEOMICS, PROMOTER, GENE EXPRESSION

MARKERS, GENE EXPRESSION CASCADE, APOPTOSIS,

RT-PCR.

Gene Expression Cascade A sequential series of individual gene expressions (i.e., each gene causing a separate/different protein to be “manufactured”), that is initiated (“set off”) by the first gene expression. For example, a gene expression cascade is often initiated by the first gene causing expression of a transcription factor (i.e., protein that itself interacts with cell’s DNA to either cause or speed up yet another gene expression). The protein resulting from that second gene expression could be yet another transcription factor that triggers another (i.e., third) gene expression, and so on. See also GENE,

EXPRESS, GENE EXPRESSION, CASCADE, PROTEIN,

CELL, DEOXYRIBONUCLEIC ACID (DNA), PROMOTER,

TRANSCRIPTION FACTORS, APOPTOSIS.

Gene Expression Markers Refers to molecules (e.g., synthesized due to a specific gene’s expression) or consequences (e.g., cell apoptosis due to a specific gene’s expression) that can be measured as proof of gene’s expression in gene expression analysis. See

also GENE EXPRESSION, GENE, GENE EXPRESSION

ANALYSIS, EXPRESS, BIOCHIPS, PROTEIN, CELL,

APOPTOSIS, GREEN FLUORESCENT PROTEIN.

Gene Expression Profiling Determination of specifically which genes are “switched on” (e.g., in a cell), thereby enabling precise

definition of the phenotypic condition of that cell (i.e., the phenotype of that cell at that moment). Typical uses (i.e., comparison of such tissue phenotypes) include:

1.Comparing diseased cell with normal cell.

2.Defining quantitatively the “normal” state.

3.Comparing a given drug’s impact (i.e., treated cell with normal cell).

4.Comparing old cell with young cell.

In subsequent gene expression analysis, the quantitative amounts of each protein being expressed can be determined via use of such technologies as two-dimensional (2D) gel electrophoresis, Southern blot analysis, fluorescence tagging, radiolabeling, RT-PCR, QPCR, plane polarimetry, etc. See also GENE,

GENE EXPRESSION, PROTEIN, CELL, PHENOTYPE,

GENE EXPRESSION ANALYSIS, TWO-DIMENSIONAL

(2D) GEL ELECTROPHORESIS, SOUTHERN BLOT

ANALYSIS, RADIOLABELED, RT-PCR, QPCR, GENE

EXPRESSION MARKERS, MICROARRAY (TESTING).

Gene Function Analysis The determination of which protein is expressed (i.e., caused to be “manufactured”) by each gene in an organism’s genome/DNA. Typically, gene function analysis follows after discovery of gene sequences found via structural genomics study. Some methods utilized to determine which proteins result from which gene(s) are:

1.Site-directed mutagenesis (SDM) to compare two same-species organisms possessing two different genes at the same site (SNP) on the genome (i.e., on organism’s DNA).

2.Antisense DNA sequences to compare two same-species organisms, one of which has a gene at the same site “turned off” (silenced) via antisense DNA.

3.Reporter gene, to compare two samespecies organisms (possessing two different genes at the same site on genome/DNA) via a reporter gene adjacent to the gene/site, to detect

© 2002 by CRC Press LLC

presence or absence of the desired trait/function.

4.Comparison of same organism (e.g., crop plant) when one of the two is “challenged” by a specific plant disease.

5.Chemical genetics, to compare two same-species organisms (one of which has gene at the specific site at least partially inactivated by a specific chemical).

6.“Silencing” or “knocking out” a particular gene via other methods than antisense or chemical genetics, to compare.

7.Use of already-known “model organisms” (e.g., Drosophila for comparing insect genes, Arabidopsis thaliana for plant genes, Caenorhabditis elegans for animal genes).

See also GENE, GENE EXPRESSION, GENETIC CODE, INFORMATIONAL MOLECULES, EXPRESS,

PROTEIN, GENOME, GENOMICS, STRUCTURAL GENOMICS, FUNCTIONAL GENOMICS, ZINC FINGER PROTEINS, TRAIT, DEOXYRIBONUCLEIC ACID

(DNA), SEQUENCE (OF A DNA MOLECULE), POINT

MUTATION, SITE-DIRECTED MUTAGENESIS (SDM),

ANTISENSE (DNA SEQUENCE), GENE SILENCING,

REPORTER GENE, METHYLATION, POSITIONAL CLONING, DNA METHYLATION, CHEMICAL GENETICS,

MODEL ORGANISM, DROSOPHILA, ARABIDOPSIS T H A L I A N A , C A E N O R H A B D I T I S E L E G A N S

(C. ELEGANS), CENTRAL DOGMA (OLD), CENTRAL

DOGMA (NEW), TRANSCRIPTION FACTORS, TRAN-

SWITCH®, SINGLE-NUCLEOTIDE POLYMORPHISMS

(SNPs).

Gene Fusion Refers to the technology/methods utilized to fuse together two or more genes. When such a “fused gene” is then inserted into a genome (e.g., the DNA of a plant), it causes production (in plant’s ribosomes) of protein(s) consisting of all or part of the amino acid sequences (known as the “domain”) of the two proteins typically coded for by those two genes. This fusion is often done in order to put expression of the second (fused) gene under the control of the (strong) promoter of the first gene. During 2001, Rajbir Sangwan and colleagues inserted a fused gene into a potato plant (Solanum tuberosum), a major source of plant starch. That fused gene coded for

production of the two proteins α-amylase and glucose isomerase; both are enzymes. α-amylase catalyzes the conversion of potato starch into glucose (a sugar), and glucose isomerase catalyzes conversion of glucose to fructose (a more valuable sugar). See

	also GENE, GENOME, DEOXYRIBONUCLEIC ACID
	(DNA), GENETIC ENGINEERING, RIBOSOMES, CODING
	SEQUENCE, PROTEIN, AMINO ACID, SEQUENCE (OF
	A PROTEIN MOLECULE), FUSION PROTEIN, EXPRESS,
	PROMOTER, ENZYME, AMYLASE, GLUCOSE,
	ISOMERASE.
	Gene Machine An instrument which, when
		G
	fed information on the amino acid sequence
	of a protein (usually via a protein
	sequencer), will automatically produce poly-
	nucleotide gene segments to code for that
	protein. See also SEQUENCING (OF DNA MOLE-
	CULES), SYNTHESIZING (OF DNA MOLECULES),
	GENE, AMINO ACID, PROTEIN.
	Gene Manipulation See GENETIC ENGINEERING.
	Gene Map See LINKAGE MAP, GENETIC MAP,
	PHYSICAL MAP (OF GENOME).
	Gene Mapping See SEQUENCING (OF DNA MOL-
	ECULES), GENETIC MAP, LINKAGE MAP, PHYSICAL
	MAP (OF GENOME).
	Gene Probe See DNA PROBE.
	Gene Repair (done by man) The “repair” of
	a damaged gene (e.g., mutation) or replace-
	ment of a given gene,via a process invented
	by Eric Kmiec in 1993. The desired DNA
	(gene) is added to a cell, along with RNA,
	in a paired-group known as a chimeraplast.
	The chimeraplast attaches itself to the cell;
	DNA at the site of the specific gene (i.e., the
	one that is to be changed), and “repairs” it
	using its (new) chimeraplast-DNA as a “tem-
	plate.” See also GENE, CHIMERAPLASTY, MUTA-
	T I O N , D E O X Y R I B O N U C L E I C A C I D ( D N A ),
	RIBONUCLEIC ACID (RNA), CELL, TEMPLATE.
	Gene Repair (natural) Refers to the natural
	processes via which all cells in an organism
	are continually repairing their DNA (which
	can be damaged by ultraviolet light, various
	chemicals, etc.). In these natural cell (gene
	repair) processes, first, an enzyme complex
	detects the damaged DNA (e.g., on one of
	the two strands of the DNA molecule). Next,
	an enzyme cuts out the damaged portion of
	the DNA (on that one strand, leaving the
	other — good — strand intact). Then a DNA

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polymerase enzyme enters the gap and synthesizes (manufactures) the new DNA (to replace the portion that was cut out), using the intact — good — DNA strand as a template.

Finally, the new DNA is joined to the old DNA via the help of DNA ligase enzyme.

See also CELL, ENZYME, DEOXYRIBONUCLEIC ACID (DNA), DNA POLYMERASE, DNA LIGASE,

TEMPLATE.

Gene Replacement Therapy See GENE DELIV-

ERY.

Gene Silencing The suppression of gene

Gexpression (e.g., of the gene for polygalacturonase which causes fruit to ripen) via a variety of methods (e.g., via chemical genetics, “zinc finger proteins,” sense or antisense

genes, etc.). See also GENE, EXPRESS, GENE

EXPRESSION, GENETIC CODE, INFORMATIONAL MOLECULES, PROTEIN, CHEMICAL GENETICS, ZINC FINGER PROTEINS, GENE FUNCTION ANALYSIS,

COSUPPRESSION, ANTISENSE (DNA SEQUENCE),

TRANSWITCH®, SENSE, POLYGALACTURONASE

(PG), GPA1.

Gene Splicing The enzymatic attachment (joining) of one gene (or part of a gene) to another; also removal of introns and splicing of exons during mRNA synthesis. See also SPLICING,

CENTRAL DOGMA (NEW), MESSENGER RNA (mRNA),

GENE, B LYMPHOCYTES, RECOMBINASE.

Gene Switching See GENE, GENETIC CODE, COD-

ING SEQUENCE, DEOXYRIBONUCLEIC ACID (DNA),

SEQUENCE (OF A DNA MOLECULE), REGULATORY

SEQUENCE, TRANSCRIPTION FACTORS, CBF1, COLD

HARDENING, CESSATION CASSETTE, SYSTEMIC

ACQUIRED RESISTANCE (SAR).

Gene Targeting See GENETIC TARGETING, GENE

SPLICING, GENE DELIVERY, GENETIC ENGINEERING.

Gene Technology Office An agency of the Australian government, established in 1997, to oversee and regulate all genetic engineering activities conducted in the country of Australia. Replaced/superceded by Australia’s newly formed Interim Office of the Gene Technology Regulator (IOGTR) in 1999.

See also IOGTR, GENE TECHNOLOGY REGULATOR

(GTR), GENETIC ENGINEERING, RECOMBINANT DNA ADVISORY COMMITTEE (RAC), ZKBS (CENTRAL COMMITTEE ON BIOLOGICAL SAFETY), INDIAN DEPARTMENT OF BIOTECHNOLOGY, COMMISSION OF BIOMOLECULAR ENGINEERING.

Gene Technology Regulator (GTR) The regulatory body of Australia’s government that is responsible for approvals of new rDNA products (e.g., new genetically engineered crops) before they can be introduced into Australia. GTR replaced Australia’s IOGTR (Interim Office of the Gene Technology Regulator) in this role on June 21, 2001. See also

INTERIM OFFICE OF THE GENE TECHNOLOGY REGULATOR (IOGTR), GENE TECHNOLOGY OFFICE,

GENETIC MANIPULATION ADVISORY COMMITTEE

(GMAC), rDNA, DEOXYRIBONUCLEIC ACID (DNA),

GENETIC ENGINEERING, RECOMBINANT DNA ADVISORY COMMITTEE (RAC), COMMISSION OF BIOMOLECULAR ENGINEERING, INDIAN DEPARTMENT OF

BIOTECHNOLOGY.

Gene Therapy See GENE DELIVERY.

Gene Transcript See TRANSCRIPT.

Generation Time The time required for a population of cells to double. The average time required for a round of cell division. See also

CELL, MITOSIS.

Genestein See GENISTEIN (Gen).

Genetic Code The set of triplet code words in DNA coding for all of the amino acids. There are more than 20 different amino acids and only four bases (adenine, thymine, cytosine, and guanine). The mRNA code is a triplet code, that is, each successive “frame” of three nucleotides (sometimes called a codon) of the mRNA corresponds to one amino acid of the protein. This rule of correspondence is the genetic code. The genetic code consists of 64 entries — the 64 triplets possible when there are four possible nucleotides, each of which can be at any of three places (4 × 4 × 4 = 64). A triplet code was required because a doublet code would have only been able to code for (4 × 4 = 16) 16 amino acids. A triplet code allows for the coding of 64 theoretical amino acids. Since only a little over 20 exist, there is some redundancy in the system. Hence some certain amino acids are coded for by two or three different triplets. See also MESSENGER

RNA (mRNA), DEOXYRIBONUCLEIC ACID (DNA),

INFORMATIONAL MOLECULES.

Genetic Engineering The selective, deliberate alteration of genes (genetic material) by man. This term has come to have a very broad meaning, including the manipulation

© 2002 by CRC Press LLC

and alteration of the genetic material (constitution) of an organism in such a way as to allow it to produce endogenous proteins with properties different from those of the traditional (historic/typical), or to produce entirely different (foreign) proteins altogether. Some other words often applicable to the same process are gene splicing, gene manipulation, or recombinant DNA technology (techniques). See also GENE, INFORMA-

TIONAL MOLECULES, CHROMOSOMES, GENE

AMPLIFICATION, VECTOR, PLASMID, AGROBACTERIUM TUMEFACIENS, GENE SPLICING, DEOXYRIBO-

NUCLEIC ACID (DNA), TRANSGENIC (ORGANISM),

BIOLISTIC R GENE GUN, WHISKER™, “SHOTGUN”

METHOD, NUCLEAR TRANSFER, GMO, RECOMBINANT

DNA (rDNA), RECOMBINATION, HETEROKARYON,

HEREDITY, MESSENGER RNA (mRNA), HETERODU-

PLEX, POSITIVE AND NEGATIVE SELECTION (PNS),

POLYMERASE CHAIN REACTION (PCR) TECHNIQUE,

BIOTECHNOLOGY, METABOLIC ENGINEERING.

Genetic Engineering Approval Committee

See GEAC.

Genetic Event See EVENT.

Genetic Linkage See LINKAGE, LINKAGE GROUP.

Genetic Manipulation See GENETIC ENGINEERING.

Genetic Manipulation Advisory Committee (GMAC) A body that advises the Australian government on matters pertaining to genetic engineering (e.g., new rDNA product approvals). The GMAC is analogous to Germany’s ZKBS (Central Commission on Biological Safety), Brazil’s CTNBio (National Technical Biosafety Commission), and the Kenya Biosafety Council. See also

GMAC, ZKBS (CENTRAL COMMISSION ON BIOLOG-

ICAL SAFETY), RECOMBINANT DNA ADVISORY

COMMITTEE (RAC), GENETIC ENGINEERING, rDNA,

DEOXYRIBONUCLEIC ACID (DNA), CTNBio, KENYA

BIOSAFETY COUNCIL, GENE TECHNOLOGY OFFICE,

GENE TECHNOLOGY REGULATOR (GTR).

Genetic Map A diagram showing the relative sequence and position of specific genes along a chromosome (DNA) molecule. Markers utilized as “signposts”/guideposts in such maps include single-nucleotide polymorphisms (SNPs), restriction sites (i.e., the specific locations where each restriction endonuclease “cuts” a DNA strand), and microsatellites. Such markers located in or

close to the gene of interest (e.g., a diseasecausing gene within a chromosome) to a researcher are more likely to be inherited along with that gene. See also POSITION

EFFECT, GENE, GENOME, CHROMOSOMES, DEOXY-

	RIBONUCLEIC ACID (DNA), PHYSICAL MAP (OF
	GENOME), SINGLE-NUCLEOTIDE POLYMORPHISMS
	(SNPs), RESTRICTION SITE, MICROSATELLITE DNA,
	MARKER ASSISTED SELECTION.
	Genetic Marker See MARKER (GENETIC MARKER).
	Genetic Probe See DNA PROBE.
	Genetic Targeting The insertion of antisense
	DNA molecules in vivo into selected cells of	G
	the body in order to block the activity of
	undesirable genes. These genes might
	include oncogenes, or genes crucial to the
	life cycle of parasites such as trypanosomes
	(which cause sleeping sickness). See also
	ANTISENSE (DNA SEQUENCE), GENE, GENE DELIV-
	ERY, ONCOGENES, DENDRIMERS.
	Genetic Use Restriction Technologies
	(GURTs) A general term refering to several
	different technologies intended to control the
	expression (or nonexpression) of the gene(s)
	for specific (e.g., valuable) traits. See also
	CESSATION CASSETTE, GENE, TRAIT, EXPRESS,
	VALUE-ENHANCED GRAINS.
	Genetically Engineered Microbial Pesticides
	(GEMP) One or more microbes that have
	been genetically engineered to be effective
	in combatting pest(s) that attack crops or
	livestock. For example, a microbe that nat-
	urally attacks a crop pest could be geneti-
	cally engineered to make the microbe more
	potent, or more durable in field environ-
	ments when applied via selected method of
	microbe application. See also MICROBE,
	GENETIC ENGINEERING, WHEAT TAKE-ALL DISEASE,
	BACULOVIRUS, BACILLUS THURINGIENSIS (B.t.),
	FEDERAL INSECTICIDE FUNGICIDE AND RODENTI-
	CIDE ACT (FIFRA), TOXIC SUBSTANCES CONTROL
	ACT (TSCA).
	Genetically Engineered Organism (GEO)
	See GEO.
	Genetically Manipulated Organism (GMO)
	See GMO.
	Genetically Modified Microorganism
	(GMM) See GMM.
	Genetically Modified Organism (GMO)
	See GMO.

© 2002 by CRC Press LLC