Search results
Results from the WOW.Com Content Network
Down syndrome. Down syndrome (United States) or Down's syndrome (United Kingdom and other English-speaking nations), also known as trisomy 21, is a genetic disorder caused by the presence of all or part of a third copy of chromosome 21. [ 3 ]
Trisomy 9; Trisomy 8 (Warkany syndrome 2) Of these, Trisomy 21 and Trisomy 18 are the most common. In rare cases, a fetus with Trisomy 13 can survive, giving rise to Patau syndrome. Autosomal trisomy can be associated with birth defects, intellectual disability and shortened life. Trisomy of sex chromosomes can also occur and include: [4]
Monosomy. Schematic karyogram of a human, showing the normal diploid karyotype. It shows annotated bands and sub-bands as used for the nomenclature of chromosome abnormalities including partial monosomies. It shows 22 homologous chromosomes, both the female (XX) and male (XY) versions of the sex chromosome (bottom right), as well as the ...
The fundamental autosomal number or autosomal fundamental number, FNa[36]or AN,[37]of a karyotype is the number of visible major chromosomal arms per set of autosomes(non-sex-linked chromosomes). Ploidy. [edit] Ploidyis the number of complete sets of chromosomes in a cell. Polyploidy, where there are more than two sets of homologous chromosomes ...
Cri du chat syndrome is due to a partial deletion of the short arm of chromosome number 5, also called "5p monosomy " or "partial monosomy." Approximately 90% of cases result from a sporadic, or randomly occurring, de novo deletion. The remaining 10–15% are due to unequal segregation of a parental balanced translocation where the 5p monosomy ...
Aneuploidy is the presence of an abnormal number of chromosomes in a cell, for example a human cell having 45 or 47 chromosomes instead of the usual 46. [ 1 ][ 2 ] It does not include a difference of one or more complete sets of chromosomes. A cell with any number of complete chromosome sets is called a euploid cell.
Homologous chromosomes are made up of chromosome pairs of approximately the same length, centromere position, and staining pattern, for genes with the same corresponding loci. One homologous chromosome is inherited from the organism's mother; the other is inherited from the organism's father. After mitosis occurs within the daughter cells, they ...
Euploidy (Greek eu, "true" or "even") is the state of a cell or organism having one or more than one set of the same set of chromosomes, possibly excluding the sex-determining chromosomes. For example, most human cells have 2 of each of the 23 homologous monoploid chromosomes, for a total of 46 chromosomes.