Full Patau syndrome is a severe genetic disorder caused by having an extra copy of genetic material from chromosome 13 in all cells of the body.
Also known as Trisomy 13, Patau syndrome is a genetic disorder in which a person has 3 copies of genetic material from chromosome 13, instead of the usual 2 copies, according to the provided reference. The term "full" Patau syndrome specifically refers to the condition where this extra copy of chromosome 13 is present in every cell.
The Genetic Basis
Our bodies are made up of trillions of cells, each containing genetic instructions organized into structures called chromosomes. Typically, humans have 23 pairs of chromosomes (46 in total). One chromosome from each pair is inherited from each parent.
- Normal State: Individuals usually have two copies of chromosome 13.
- Patau Syndrome: In Patau syndrome, there is an extra copy of chromosome 13, resulting in three copies instead of two.
This additional genetic material disrupts normal development, leading to the characteristic features and health challenges associated with the syndrome.
Understanding "Full" Patau Syndrome
While the reference defines the core condition, the term "full" Patau syndrome distinguishes it from other less common forms:
- Full Trisomy 13 (Full Patau Syndrome): The extra chromosome 13 is present in all cells of the body. This is the most common type and is usually caused by an error during the formation of egg or sperm cells.
- Mosaic Trisomy 13: The extra chromosome 13 is present in only some of the body's cells. This can lead to a less severe presentation of the syndrome, depending on the proportion and location of cells with the extra chromosome.
- Partial Trisomy 13: Only a part of chromosome 13 is duplicated. This is rare and can occur if a piece of chromosome 13 breaks off and attaches to another chromosome, or if a piece is duplicated.
The reference notes that rarely, the extra material may be attached to another chromosome (translocation). This describes one way partial Trisomy 13 or, less commonly, full Trisomy 13 can occur due to structural rearrangement rather than an extra whole chromosome.
Key Facts About Full Patau Syndrome
Here are some essential points about the genetic condition:
| Aspect | Description |
|---|---|
| Cause | Presence of an extra third copy of chromosome 13. |
| Type | A trisomy, meaning three copies instead of two. |
| "Full" | Implies the extra chromosome is in all cells. |
| Also Known As | Trisomy 13. |
| Impact | Causes severe developmental abnormalities. |
Why is Genetic Material Important?
Chromosomes contain genes, which are the instructions for building and operating the body. Having an extra copy of an entire chromosome means there are extra copies of all the genes located on that chromosome. This excess genetic information interferes with normal development, leading to severe birth defects affecting multiple organ systems, including the brain, heart, and face.
Understanding the genetic cause, as described by the presence of three copies of chromosome 13, is fundamental to understanding full Patau syndrome.
