Chromosomal abnormalities

chromosomal condition

human disease

abnormal number or structure of chromosomes

human disease

phenomenon that results in unusual rearrangement of chromosomes

Aneuploidy is the presence of an abnormal number of chromosomes in a cell, for example a human somatic cell having 45 or 47 chromosomes instead of the usual 46. 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.

A trisomy is a type of polysomy in which there are three instances of a particular chromosome, instead of the normal two. A trisomy is a type of aneuploidy (an abnormal number of chromosomes).

reordering of genes in a DNA-sequence

thumb|Schematic karyotype|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 mitochondrial genome (to scale at bottom left).]] Monosomy is a form of aneuploidy with the presence of only one chromosome from a pair. Partial monosomy occurs when a portion of one chromosome in a pair is missing.

syndrome characterized by overgrowth (macrosomia), an increased risk of childhood cancer and congenital malformations

rare congenital condition where an individual with XX chromosomes is born with a penis and testes

chromosome whose arms fused into a ring

chromosome abnormality involving a change in the structure of the native chromosome

chromosomal rearrangement in pairs 13, 14, 15, 21, and 22

rare disease

Abnormal small fragment of a chromosome

A tetrasomy is a form of aneuploidy with the presence of four copies, instead of the normal two, of a particular chromosome.

Nullisomic is a genetic condition involving the lack of both the normal chromosomal pairs for a species (2n-2). Humans with this condition will not survive.

type of genomic instability

thumb|Human karyotype|karyogram, with annotated bands and sub-bands. It is a graphical representation of the idealized human [[diploid karyotype. It shows dark and white regions on G banding. Each row is vertically aligned at centromere level. It shows 22 homologous autosomal chromosome pairs, both the female (XX) and male (XY) versions of the two sex chromosomes, as well as the mitochondrial genome (at bottom left). ]] thumb|right|Trisomy 21 – Down syndrome, an example of a polysomy at chromosome 21 Polysomy is a condition found in many species, including fungi, plants, insects, and mammals,