Photographic display of total chromosome complement in a cell
"Idiogram" redirects here. Not to be confused with ideogram.
A karyotype is the general appearance of the complete set of chromosomes in the cells of a species or in an individual organism, mainly including their sizes, numbers, and shapes.[1][2]Karyotyping is the process by which a karyotype is discerned by determining the chromosome complement of an individual, including the number of chromosomes and any abnormalities.
Micrographic karyogram of human male using Giemsa stainingSchematic karyogram demonstrating the basic knowledge needed to read a karyotype
A karyogram or idiogram is a graphical depiction of a karyotype, wherein chromosomes are generally organized in pairs, ordered by size and position of centromere for chromosomes of the same size. Karyotyping generally combines light microscopy and photography in the metaphase of the cell cycle, and results in a photomicrographic (or simply micrographic) karyogram. In contrast, a schematic karyogram is a designed graphic representation of a karyotype. In schematic karyograms, just one of the sister chromatids of each chromosome is generally shown for brevity, and in reality they are generally so close together that they look as one on photomicrographs as well unless the resolution is high enough to distinguish them. The study of whole sets of chromosomes is sometimes known as karyology.
Karyotypes describe the chromosome count of an organism and what these chromosomes look like under a light microscope. Attention is paid to their length, the position of the centromeres, banding pattern, any differences between the sex chromosomes, and any other physical characteristics.[3] The preparation and study of karyotypes is part of cytogenetics.
The basic number of chromosomes in the somatic cells of an individual or a species is called the somatic number and is designated 2n. In the germ-line (the sex cells) the chromosome number is n (humans: n = 23).[4][5]p28 Thus, in humans 2n = 46.
So, in normal diploid organisms, autosomal chromosomes are present in two copies. There may, or may not, be sex chromosomes. Polyploid cells have multiple copies of chromosomes and haploid cells have single copies.
Karyotypes can be used for many purposes; such as to study chromosomal aberrations, cellular function, taxonomic relationships, medicine and to gather information about past evolutionary events (karyosystematics).[6]
^"Karyotype, definition". Collins English Dictionary. Retrieved 23 December 2022.
^Judd, Walter S.; Campbell, Christopher S.; Kellogg, Elizabeth A.; Stevens, Peter F.; Donoghue, Michael J. (2002). Plant systematics, a phylogenetic approach (2 ed.). Sunderland MA, US: Sinauer Associates Inc. p. 544. ISBN 0-87893-403-0.
^King, R.C.; Stansfield, W.D.; Mulligan, P.K. (2006). A dictionary of genetics (7th ed.). Oxford University Press. p. 242.
^White 1973, p. 35
^Stebbins, G.L. (1950). "Chapter XII: The Karyotype". Variation and evolution in plants. Columbia University Press. ISBN 9780231017336.
A karyotype is the general appearance of the complete set of chromosomes in the cells of a species or in an individual organism, mainly including their...
Trisomy X, also known as triple X syndrome and characterized by the karyotype 47,XXX, is a chromosome disorder in which a female has an extra copy of...
Virtual karyotype is the digital information reflecting a karyotype, resulting from the analysis of short sequences of DNA from specific loci all over...
Biobank found women with 45,X0 karyotypes to have an average height of 145 cm (4 ft 9 in), while those with 45,X0/46,XX karyotypes averaged 159 cm (5 ft 2+1⁄2 in)...
lifetime. There are 47 chromosomes, instead of the usual 46, giving a 47,XYY karyotype. Treatment may include speech therapy or extra help with schoolwork, however...
child with KS. The syndrome is diagnosed by the genetic test known as a karyotype. The Klinefelter syndrome has different manifestations and these will...
pairs of chromosomes needed to form a normal cell with a typical human karyotype of 46 chromosomes. Numerical errors can arise at either of the two meiotic...
variation in karyotype may occur during development from the fertilized egg. The technique of determining the karyotype is usually called karyotyping. Cells...
analysis. Metaphase chromosomes make the classical picture of chromosomes (karyotype). For classical cytogenetic analyses, cells are grown in short term culture...
as Swyer syndrome, is a type of defect hypogonadism in a person whose karyotype is 46,XY. Though they typically have normal vulvas, the person has underdeveloped...
occurs via nondisjunction, a random event in gamete development. The karyotype observed in the syndrome is formally known as 49,XXXYY, which represents...
agenesis is a rare condition where an individual lacks both gonads. If the karyotype is 46,XY and the individual otherwise has a male phenotype, it is called...
detected or confirmed by comparing an individual's karyotype, or full set of chromosomes, to a typical karyotype for the species via genetic testing. Sometimes...
nondisjunction during gamete or zygote development. The formal term for the karyotype observed in tetrasomy X is 48,XXXX, as the condition is typified by a...
contrasting with the most typical snake karyotype with a stable chromosomal number of 2 n = 36 . The karyotype includes heteromorphic ZZ/ZW sex chromosomes...
testosterone appears to be associated. All adult men with a non-mosaic 48,XYYY karyotype known to the medical literature have been azoospermic, though one man...
rare congenital intersex condition in which an individual with a 46,XX karyotype develops a male phenotype. Synonyms include 46,XX testicular difference...
their behaviour during mitosis and meiosis. Techniques used include karyotyping, analysis of G-banded chromosomes, other cytogenetic banding techniques...
chromosome 21 (in addition to their normal chromosomes). A typical human karyotype is shown here. Every chromosome has two copies. In the bottom right, there...
evolutionary history. A karyotype is the characteristic chromosome complement of a eukaryote species. The preparation and study of karyotypes is part of cytology...
DNA sequencing, and DNA microarrays, and cytogenetic methods such as karyotyping and fluorescence in situ hybridisation. DNA sequencing is essential to...
1966). London Conference (1963): "London Conference on the Normal Human Karyotype." Cytogenetics 2:264–268 (1963) Denver Conference (1960): "A proposed...
rare cases, it may be related to a parent's chromosomal mosaicism. The karyotype observed in pentasomy X is formally known as 49,XXXXX, which represents...
in the human genome which retain synteny with the ancestral chordate karyotype. Synteny analysis indicates that there were 17 chromosomes in the last...
constitute 20 to 80% of the LOH seen in human tumors. Determination of virtual karyotypes using SNP-based arrays can provide genome-wide copy number and LOH status...
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