What is Down Syndrome? And How Can It Be Detected?
Down syndrome is one of the most famous genetic disorders that affects a significant number of people. Through this article, we will closely explore the nature of Down syndrome, how it occurs, and the most important signs that distinguish individuals with Down syndrome. Here are the details.
What is Down Syndrome?
Down syndrome is a genetic disorder that affects chromosome 21, which undergoes partial or complete abnormal divisions. This causes the affected individual to acquire specific physical characteristics and developmental changes that distinguish people with Down syndrome.
It is important to know that Down syndrome varies in severity. In some patients, it may appear with physical changes only or may be accompanied by intellectual disability and developmental delay.
This syndrome causes learning disabilities in children, affects digestive system functions, and leads to heart disorders and many other medical problems.
What are the Symptoms of Down Syndrome?
There are some features that distinguish the appearance of individuals with Down syndrome. Among these are:
Small head.
Flat face.
Protruding tongue.
Short neck.
Slanted palpebral fissures.
Small, unusually shaped ears.
Short hands with a single crease across the palm.
Poor muscle tone (hypotonia).
Excessive flexibility.
Small hands and feet with relatively short fingers.
Small white spots that appear on the iris of the eye, known as Brushfield spots.
Causes of Down Syndrome
Normal human cells contain 23 pairs of chromosomes, with one chromosome from the father and another from the mother.
People develop Down syndrome when there is a partial or complete extra copy of chromosome 21, which contains genetic material responsible for the characteristic features of Down syndrome.
Below are the three genetic variations that can cause Down syndrome:
Trisomy 21:
95% of cases result from this cause. The child has three copies of chromosome 21 instead of two. This occurs during the division of the egg or sperm cell.
Mosaic Down Syndrome:
This is a rare form of Down syndrome, where only some cells contain an extra copy of chromosome 21, while the remaining cells are normal. This usually occurs due to abnormal cell division after fertilization.
Translocation Down Syndrome:
This type of Down syndrome occurs when part of chromosome 21 attaches to another chromosome before or during pregnancy. These individuals have two normal copies of chromosome 21, plus extra genetic material from chromosome 21 attached to another chromosome.
Is Down Syndrome Hereditary?
Usually, Down syndrome is not inherited and results from a cell division error during fetal development. However, translocation Down syndrome can be passed from parents to children, at a rate of 3 to 4 among all children with translocation Down syndrome.
It is worth mentioning that when children inherit a balanced translocation, they have some rearranged genetic material from chromosome 21, which is not considered extra genetic material. This means that the balanced carrier does not show any symptoms of Down syndrome, but they can pass it on to their children, causing Down syndrome.
Risk Factors for Down Syndrome
Delayed childbearing, as advancing age increases the chances of incorrect chromosomal division in eggs.
If one of the parents carries a genetic translocation for Down syndrome.
If the parents have a previous experience of having a child with Down syndrome.
Complications of Down Syndrome
There are some potential complications of Down syndrome, including:
Congenital heart defects, which can sometimes be life-threatening.
Gastrointestinal defects, which may include abnormalities in the intestines, esophagus, anus, or trachea.
Immune system disorders, such as autoimmune diseases, infectious diseases, or cancers.
Obesity.
Spinal cord problems, such as atlantoaxial instability.
Leukemia.
Early-onset dementia, with signs beginning around age fifty.
Other problems, such as endocrine problems, dental problems, and sensory problems.
How to Cope with Down Syndrome
Consult a team of specialists to provide medical support regarding the child’s physical problems.
Ask healthcare providers about programs for people with Down syndrome to develop language, motor, and social skills.
Explore the educational options available for your child, whether regular classes, special classes, or both.
Involve your child in social and recreational activities to develop their skills.
Continuously encourage your child to be independent and rely on themselves in performing basic tasks.