Understanding Down Syndrome: Types, Symptoms and Treatment Options

Types of Down Syndrome

Down syndrome is a genetic disorder caused by the presence of an extra copy of chromosome 21. While there is one general classification of Down syndrome, there are three main types based on how the extra chromosome 21 occurs. These types include:

1. Trisomy 21

Trisomy 21 is the most common type of Down syndrome, accounting for approximately 95% of cases. It occurs when there is a full or extra copy of chromosome 21 in every cell of the body. This additional genetic material leads to the physical and cognitive characteristics associated with Down syndrome.

2. Mosaic Down Syndrome

Mosaic Down syndrome is a less common type, occurring in about 1-2% of individuals with Down syndrome. In this type, the extra copy of chromosome 21 is present in some cells, but not all. The presence of the extra chromosome can vary among different tissues and organs, resulting in a wide range of symptoms and abilities among individuals with mosaic Down syndrome.

3. Translocation Down Syndrome

Translocation Down syndrome accounts for approximately 3-4% of cases. It occurs when a portion of chromosome 21 breaks off during cell division and attaches itself to another chromosome, typically chromosome 14. As a result, individuals with translocation Down syndrome have the extra genetic material from chromosome 21, but it is attached to a different chromosome. Translocation Down syndrome can be inherited from a parent who carries a balanced translocation or can occur spontaneously.

It’s important to note that regardless of the type of Down syndrome, individuals may experience a range of physical, cognitive, and developmental characteristics. However, the specific symptoms and abilities can vary widely among individuals, making each person with Down syndrome unique.

It’s recommended to consult with healthcare professionals, such as geneticists or pediatricians, for accurate diagnosis, information, and support for individuals with Down syndrome and their families.