| germ line gene therapy | The repair or replacement of a defective gene within the gamete-forming tissues, which produces an inheritable change in an organisms genetic constitution. (09 Oct 1997) |
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| germ-line mutation | Any detectable and heritable alteration in the lineage of germ cells. Mutations in these cells (i.e., "generative" cells ancestral to the gametes) are transmitted to progeny while those in somatic cells are not. (12 Dec 1998) |
| germ line transformation | Micro injection of foreign DNA into an early embryo, so that it becomes incorporated into the germ line of the individual and thus stably inherited in subsequent generations of transgenic organisms. Typically, the DNA would be a reporter gene or cDNA in a vector such as a transposon, that might also carry a visible marker gene such as eye or coat colour), so that successful transformation could readily be detected. (18 Nov 1997) |
| germ nucleus | <cell biology> The smaller nucleus in ciliate protozoans, fully active in inheritance and passed after meiosis to conjugating pairs. Gives rise to the macronucleus or macronuclei. Genes in the micronucleus are not actively transcribed. (18 Nov 1997) |
| germ plasm | The liquid portion of a gamete (egg or sperm) that contains genetic material. (09 Oct 1997) |
| germ theory | The theory, now a doctrine, that infectious diseases are due to the presence and functional activity of microorganisms within the body. (05 Mar 2000) |
| germ tube | A young hypha growing out of a yeast cell or spore, the beginning of a mycelium; also used as a rapid test for differentiating Candida albicans from other Candida species. (05 Mar 2000) |
| germ tube test | A test for the identification of Candida albicans; after a 3-hr incubation in serum, an inoculum of Candida develops tubelike appendages. (05 Mar 2000) |
| Weismann germ plasm theory | <genetics> The theory that organisms maintain genetic continuity from organism to offspring through the germ line cells (germ plasm) and that the other (somatic) cells play no part in the transmission of heritable factors. (18 Nov 1997) |
| primordial germ cell | The most primitive undifferentiated sex cell, found initially outside the gonad. Synonym: gonocyte. (05 Mar 2000) |
| neoplasms, germ cell and embryonal | Neoplasms composed of primordial germ cells of embryonic gonads or of elements of the germ layers of the embryo. The concept does not refer to neoplasms located in the gonads or present in an embryo or foetus. (12 Dec 1998) |
| dental germ | The collective tissues from which an entire tooth is formed, including the dental sac, enamel organ, and dental papilla. (12 Dec 1998) |
| tooth germ | The collective tissues from which an entire tooth is formed, including the dental sac, enamel organ, and dental papilla. (12 Dec 1998) |
| enamel germ | The enamel organ of a developing tooth; one of a series of knoblike projections from the dental lamina, later becoming bell-shaped and receiving in its hollow the dental papilla. Reserve tooth germ, enamel organ and papilla of a permanent tooth. Tooth germ, the enamel organ and dentin papilla, constituting the developing tooth. Synonym: dental germ. Wheat germ, the embryo of wheat; contains thiamine, riboflavin, and other vitamins. (05 Mar 2000) |