Down Syndrome is the condition of having an extra copy of the 21st chromosome and is one of the common chromosomal disorders. In most cases, Down Syndrome is accompanied by learning and mental problems. Developmental problems in individuals with Down Syndrome last a lifetime and thus life expectancy may be shortened. However, recently, with the development of medicine as well as social and cultural supports, individuals with Down Syndrome can lead a healthy and long life.
What Are the Characteristics of Individuals with Down Syndrome?
The prominent physical characteristics of individuals with Down Syndrome can be listed as follows:
The developmental delay in mental and social skills of children with Down Syndrome can cause impulsive behaviours, poor judgment, shortened attention span and slow learning.
Types of Down Syndrome
There are three types of Down Syndrome. These types can be described as follows:
95% of cases are of this type. Each cell in the body has three copies of 21st chromosome. The third copy of the 21st chromosome is also an independent chromosome.
In this type, either part or all of the extra 21st chromosome is attached to another chromosome.
In this case, some of the cells in the body carry two copies of the 21st chromosome as they should, while some cells have an extra 21st chromosome.
