| chromosome abnormalities | Defects in the structure or number of chromosomes resulting in structural aberrations or manifesting as disease. (12 Dec 1998) |
|---|---|
| chromosome band | A region of darker or contrasting staining across the width of a chromosome; the pattern of band's is characteristic for most chromosomes. (05 Mar 2000) |
| chromosome banding | Staining of bands, or chromosome segments, allowing the precise identification of individual chromosomes or parts of chromosomes. Applications include the determination of chromosome rearrangements in malformation syndromes and cancer, the chemistry of chromosome segments, chromosome changes during evolution, and, in conjunction with cell hybridization studies, chromosome mapping. (12 Dec 1998) |
| chromosome breakage | A type of chromosomal aberration which may result from spontaneous or induced breakage. Alkylating agents, various types of irradiation, and chemical mutagens have been found to cause induced chromosomal breakage. Breakage can induce base pair translocations, deletions, or chromatid breakage. (12 Dec 1998) |
| chromosome complement | The whole set of chromosomes for the species. In humans, the chromosome complement (which is also called the karyotype) consists of 46 chromosomes. (12 Dec 1998) |
| chromosome condensation | <cell biology> The tight packing of DNA into chromosomes in metaphase, in preparation for cell division. (18 Nov 1997) |
| chromosome deletion | Actual loss of a portion of the chromosome. (12 Dec 1998) |
| chromosome disorder | An abnormal condition due to an abnormality of the chromosomes. For example, Down syndrome (the genetic abnormality featuring three chromosome 21s, instead of two, also refered to as trisomy 21) is a chromosome disorder. (12 Dec 1998) |
| chromosome fragile sites | Heritable sensitive regions of chromosomes which show up in vitro as non-staining bands. They are associated with chromosome breakage and other aberrations, and, when located on sex chromosomes, they produce phenotypic abnormalities. No abnormal phenotype has been definitely identified with autosomal fragile sites, but some rare autosomal recessive disorders may be due to homozygosity for fragile sites. Fragile sites are designated by the letters "fra" followed by the designation for the specific chromosome and locus. (12 Dec 1998) |
| chromosome map | The chart of the linear array of genes on a chromosome. The Human Genome Project aims to map all of the human chromosomes. (12 Dec 1998) |
| chromosome mapping | The mapping of the relative locations of genes on a chromosome by analysing linkage frequencies (how often different genes are inherited together) and crossover frequencies (how often different combinations of three or more genes are inherited) or recombination frequencies. (09 Oct 1997) |
| chromosome mosaicism | See: mosaic. (05 Mar 2000) |
| chromosome painting | Application of in situ hybridisation to determine chromosomal location of genes using fluorescently tagged probes. (18 Nov 1997) |
| chromosome pair | Two chromosomes of the full diploid karyotype that are similar in form and function but that usually differ in content, one normally being inherited from each parent and one being transmitted to each progeny; in the heteromorphic sex (in humans, the male), one pair, the sex chromosomes, differ markedly in appearance, content, and function. (05 Mar 2000) |
| chromosome pairing | The process in synapsis whereby homologous chromosome's align opposite each other before disjoining in the formation of the daughter cell; the apposition permits exchange of genetic material in crossing-over. (05 Mar 2000) |