Every cell of the human body contains a nucleus, in which genetic material is stored within genes. These genes carry the codes which are responsible for all of our inherited traits. Genes are grouped along a rod-shaped structure called a chromosome. Each cell within a person’s body contains their DNA or genetic code, which usually consists of 23 pairs of chromosomes — with one of the chromosomes in each pair comes from the child’s mother and the other from the child’s father. These 46 chromosomes are an individual’s genetic blueprint — the thing that makes them who they are, determining thecharacteristics like personality traits, eye color, and inherited risk of different diseases.
The human body relies on having just the right number of chromosomes (as they carry bundles of genes). Down syndrome is a pathology that occurs when an individual has a partial or full extra copy of chromosome 21. This extra chromosome causes several issues that affect you both physically and mentally.
As the 21st chromosome contains 350 genes, and most probably all of them contribute to Down syndrome. So it is a pretty complex disorder.
This extra genetic material affects the course of development. Some of the common physical traits related to Down syndrome are small stature, low muscle tone, a single deep crease along the center of the palm, and an upward slant to the eyes– although each individual with Down syndrome is a unique person and may possess these traits to different degrees, or not at all.
The extra chromosome is present within a person from the moment of conception, so there is no chance that a person can develop Down syndrome after birth or later in life, so either you have down syndrome at birth or don’t have it.
The severity of Down syndrome varies among individuals, causing developmental delays and lifelong intellectual disability. It’s the most common form of a genetic disorder and causes learning disabilities in children. It also causes many other medical abnormalities, including gastrointestinal and heart diseases.
Early interventions and a better understanding of Down syndrome can increase the quality of life for adults and children with this disorder and help them live better lives.
Unlike many other lifelong disabilities with shorter life expectancy, Down syndrome patients can live fulfilling and healthy lives. Recent advancements in medical fields and institutional and cultural support for people with Down syndrome and their families increased the opportunities to help reduce the challenges of this condition.
1What causes Down syndrome?
All people with Down syndrome contain an extra pair of chromosome 21 present in their all or some cells, regardless of their type of Down syndrome. This additional genetic chromosomal material affects development and leads to the characteristics associated with Down syndrome.
The cause of the presence of an extra full or partial chromosome is still unknown. Maternal age is considered the only factor that can increase the chance of having a child with Down syndrome resulting from mosaicism or nondisjunction. However, as the birth rates are higher in younger women, almost 80% of babies with Down syndrome are born to mothers under 35.
There is no definite scientific research that shows that the cause of Down syndrome is environmental factors or any parents’ activity before or during pregnancy. The additional full or partial copy of chromosome 21, which leads to Down syndrome, can originate from either the mother or the father. Around 5% of the cases have been tracked down to the father.
People with Down syndrome may face mild to severe cognitive delays. They also have some same physical traits like small stature, upward-slanting eyes, and an inability to gain muscle tone, although the severity of these degrees can differ. To understand this condition, it’s essential to know all of the possible causes of Down syndrome and its risk factors.
There are usually three types of Down syndrome, each has different causes, and trisomy 21 is the most common among these. In this condition (trisomy 21), a random error occurs during cell division. This error is termed as “nondisjunction.” Generally, each pair of chromosomes from the mother and father separate at conception to form one-half of the feotal’s chromosomes’ pair. While in trisomy 21, one of the pairs of 21st chromosomes does not get separated. This results in the three 21st chromosomes in the embryo instead of two, which replicates throughout development.