| ARPKD | autosomal recessive polycystic kidney disease |
|---|---|
| ARSACS | autosomal recessive spastic ataxia of Charlevoix-Saguenay |
| PHAVER | pterygia-heart defects-autosomal recessive inheritance-vertebral defects-ear anomalies-radial defect... |
| MEN | Multiple Endocrine Neoplasia ; AD Trait 1. MEN Type I(= Wermer Syndro... |
| PBT | Paul-Bunnell test; phenacetin breath test; piebald trait; profile-based therapy |
| recessive oncogene | <molecular biology> A single copy of this gene issufficient to suppress cell proliferation, the loss of both copies of the gene contributes to cancer formation. (09 Oct 1997) |
|---|---|
| recessive, x-linked | A gene on the X chromosome that expresses itself only when there is no different gene present at that locus (spot on the chromosome). For example, duchenne muscular dystrophy (dmd) is an x-linked recessive disorder. A dmd boy has the dmd gene on his sole x chromosome (and so is said to be hemizgous for dmd). Although it is much rarer, a girl can have dmd (by several different means as, for example, if she has the dmd gene on both her x chromosomes and so is homozygous for dmd). (12 Dec 1998) |
| Bombay trait | A rare recessive trait at a locus that ordinarily manufactures H substance, the precursor from which the A and B phenotypes are elaborated; the mutant causes failure to produce H substance and no matter what the genotype at the ABO locus, the phenotype is O. The Bombay phenomenon is epistatic to the ABO locus. Origin: Bombay, India, where first reported (05 Mar 2000) |
| galtonian trait | A quantitative genetic trait due to contributions from many more of less equally important loci that resembles a continuous trait. (05 Mar 2000) |
| marker trait | A trait that may be of little importance in itself but which by association, linkage, or other means facilitates the detection, anticipation, or understanding of a disease or (for genetic diseases) the localization of the causative gene on the karyotype. (05 Mar 2000) |
| categorical trait | <genetics> A feature that can conveniently and effectively be analyzed by sorting into classes either because there is no satisfactory way of measuring it (as with blood groups) or because it falls into natural classes so that the variation among classes far exceeds that within classes (e.g., the phenotypic effects of many enzyme polymorphisms); existence of categories suggests but does not prove the operation of a major, simple, underlying cause. Synonym: qualitative trait. (05 Mar 2000) |
| penetrant trait | A trait that in the appropriate genotypes is phenotypically manifest; strictly, it is the trait that is penetrant, not the gene. See: penetrance. (05 Mar 2000) |
| mendelian trait | A categorical trait that segregates in accordance with a single-locus genetic system. (05 Mar 2000) |
| chromosomal trait | A trait dependent on a recurrent chromosomal aberration. (05 Mar 2000) |
| codominant trait | See: codominant. (05 Mar 2000) |
| sickle cell trait | <haematology> This condition occurs in people who have one of two possible genes (i.e., they are heterozygous forthe allele) that code for the defective haemoglobin responsible for sickle cell anaemia. The coditionis diagnosed by exposing an individual's red blood cells to a low oxygen environment, if the trait is present, the cells will turn to a sickle shape. People with this trait may suffer milder symptoms of sickle cell anaemia, or may have no symptoms. Some scientists believe the trait actually provides an evolutionary advantage in tropical environments because the slightly altered shape of the blood cells causes a person to be more resistant to malaria. (09 Oct 1997) |
| nonpenetrant trait | A genetic trait that is not phenotypically manifest because of non-genetic factors it therefore does not include recessivity, epistasis, hypostasis, or parastasis but does include environmental factors and pure random effects such as lyonization. (05 Mar 2000) |
| dominant lethal trait | Trait, expressed in the phenotype if present in the genotype, that precludes having descendants. All such cases are necessarily sporadic and must represent new mutations as the usual methods of classical genetics provide no means of demonstrating any genetic component whatsoever, except for tenuous arguments such as advanced paternal age. Molecular biology may help although the methods may be tedious; if there is an epistatic gene that may mask the trait, the logic is more tractable, though complex. (05 Mar 2000) |
| dominant trait | An outstanding mental or physical characteristic. See: dominance of traits. (05 Mar 2000) |
| qualitative trait | <genetics> A feature that can conveniently and effectively be analyzed by sorting into classes either because there is no satisfactory way of measuring it (as with blood groups) or because it falls into natural classes so that the variation among classes far exceeds that within classes (e.g., the phenotypic effects of many enzyme polymorphisms); existence of categories suggests but does not prove the operation of a major, simple, underlying cause. Synonym: qualitative trait. (05 Mar 2000) |