遗传学 名词解释

Homologous chromosome 同源染色体: two chromosomes, one of paternal origin, the other of maternal origin, that are identical in appearance and pair during meiosis

Inbreeding, consanguineous marriage近亲婚配:the mating of closely related individuals or of individuals having closely similar genetic constitutions.

Multiple alleles 复等位基因: three or more alleles of the same gene in homologous chromosome

Genome, chromosome set 染色体组: the complete set of genes in the chromosomes of each cell of a specific organism, the complement of genetic information in a chromosome set.

Gene 基因: the unit of heredity that is made of a DNA sequence occupying a specific location on a chromosome and codes for a polypeptide chain.

Genotype 基因型:the genetic constitution of an organism, the genetic information carried by a pair of alleles which determines a particular characteristic.

Heterozygote 异形合子:describing an individual in whom the members of a pair of genes determining a particular characteristic are dissimilar.

genetic disease 遗传病:a general term for any disorder caused by a genetic mechanism, comprising chromosome aberrations, mendelian disorders, and multifactorial disorders.

multifactoral disease 多因子病: one caused by the interaction of genetic and sometimes also nongenetic, environmental factors, e.g diabetes mellitus.

Karyotype 核型:a complete set of all the metaphase chromosomes in acell, the chromosome set of an individual or species described in terms of both the number and structure of the chromosomes.

Reciprocal translocation相互易位:the complete exchange of fragments between two broken nonhomologous chromosomes, one part of one uniting with part of the other, with no fragments left over.

Robertsonian translocation罗伯逊易位:translocation involving two acrocentric chromosomes, which fuse at the centromere region and lose their short arms.

missense mutation错义突变: A mutation in which a base change or substitution results in a codon that causes insertion of a different amino acid into the growing polypeptide chain, giving rise to an altered protein.

genetic marker遗传标记: A gene or DNA sequence having a known location on a chromosome and associated with a particular gene or trait. Genetic markers associated with certain diseases can be used to determine whether an individual is at risk for developing an inherited disease.

Centimorgan 厘摩:a unit of chromosome length, used in genetic mapping, equal to the length of chromosome over which crossing over occurs with 1 per cent frequency.

Marker chromosome标记染色体:is a structurally abnormal chromosome in which no part can be identified. The significance of a marker is very variable as it depends on what material is contained within the marker.

tumor suppressor gene 肿瘤抑制基因:is a gene that protects a cell from one step on the path to cancer. When this gene is mutated to cause a loss or reduction in its function, the cell can progress to cancer, usually in combination with other genetic changes.

Mosaic嵌合体:the presence in an individual of cells derived from the same zygote, but differing in chromosomal constitution.

Expressivity 表现度: the extent to which a heritable trait is manifested by an individual carrying the principal gene or genes that determine it.

Maternal inheritance母系遗传: the transmission of characters that are dependent on peculiarities of the egg cytoplasm produced, in turn, by nuclear genes.

Liability 易患性: is a genetic affectation which influences the phenotype of an individual organism within a species or population but by definition that phenotype can also be modified by theenvironmental conditions. In the rest of the population, conditions cannot have that affect.

fusion gene融合基因: is a hybrid gene formed from two previously separate genes. It can occur as the result of a translocation, interstitial deletion, or chromosomal inversion. Often, fusion genes are oncogenes.

dynamic mutation 动态突变: is an unstable heritable element where the probability of mutation is a function of the number of copies of the mutation. That is, the replication product of a dynamic mutation has a different likelihood of mutation than its predecessor.