What the KARYOTYPE Results Mean ?
Some chromosomal disorders that may be detected by Karyotype include:
- Down syndrome (Trisomy 21), caused by an extra chromosome 21
- Edwards syndrome (Trisomy 18), caused by an extra chromosome 18.
- Patau syndrome (Trisomy 13), caused by an extra chromosome 13.
- Klinefelter syndrome, caused by an extra X chromosome, the most common sex chromosome abnormality in males
- Turner syndrome, caused by missing one X chromosome in females.
- Chronic myelogenous leukemia (blood cancer), a classic 9:22 translocation that is diagnostic of the disease.
Different Type of Chromosome Abnormalities
| TRISOMY | This is the presence of an extra chromosome, a third instead of a pair. Diseases associated with Trisomies include Down syndrome (associated with a Trisomy of chromosome 21), Patau syndrome (Trisomy 13), Edward syndrome (Trisomy 18), and Klinefelter syndrome (a male with an extra X chromosome – XXY instead of XY) and other sex chromosome abnormalities due to extra copy of sex chromosomes. |
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| MONOSOMY | This is the absence of one of the chromosomes. A most common example of monosomy is Turner syndrome (a female with a single X chromosome – X instead of XX). Most other monosomies are not compatible with life may lead to spontaneous abortion |
| DELETIONS | These are missing pieces of chromosomes and/or genetic material. Some may be small and difficult to be detected. It can represented as segment of chromosome with deletion in long or short arm of the chromosome. |
| DUPLICATIONS | These are represent extra genetic material and may be present on any chromosome, such as the presence of two horizontal bands at a specific location instead of one. |
| TRANSLOCATIONS | With translocations, pieces of chromosomes break off and reattach to another chromosome. If it is a one-to-one switch and all of the genetic material is present (but in the wrong place), it is said to be a balanced translocation. If it is not, then it is called an unbalanced translocation. |
| GENETIC REARRANGEMENT | In this situation, genetic material is present on a chromosome but not in its usual location. A person could have both a rearrangement and a duplication or deletion. An almost infinite number of rearrangements are possible. Interpreting the effects of the changes can be challenging. |
