Know The Facts About Down Syndrome

Down syndrome is a disorder related to the abnormal number of chromosomes. It is associated with the presence of an extra chromosome. The normal set of chromosomes in an individual is 23 pairs, while in a person with Down syndrome, it becomes 23 pairs + 1 i.e 47. Trisomy of chromosome number 21 occurs in this condition, hence known as Trisomy 21. The disease is congenital, thus affecting the physical and mental growth of the baby since birth. 

Important facts associated with Down Syndrome include the following :

The incidence of Down syndrome is one per 700 births 

Down syndrome is one of the most commonly occurring chromosomal disorders, especially in the United States. The rate of incidence of the disease in the U.S has been found to be one in 700 births which means around 6000 babies are born with Down syndrome each year.

There are three types of Down syndrome:

• Trisomy 21 - This is the commonest type of Down syndrome. The presence of an extra copy of chromosome 21 is the main feature. The condition is found in 95 per cent of the cases.

• Translocation - It occurs in 3 percent of the cases, characterized by the attachment of a partial or whole chromosome to a different chromosome.

• Mosaic - Only 2 percent of the cases of Down syndrome occur in Mosaic form. It is characterized by the presence of three copies of chromosome 21 in some cells while two copies in some.

Down syndrome has been represented in historical paintings of the 15th and 16th centuries

Evidence of Down syndrome has been found in ancient paintings as well as pottery, thus confirming its occurrence 2500 years ago. The characteristic facial features have been depicted in these historical findings.

Prenatal screening for the disease is available

Down syndrome can be detected in prenatal screening under the supervision of a specialist. The screening can be done in two ways - maternal blood tests and ultrasound. Women who are 35 years or older than that usually need to undergo such tests. It is followed by methods like amniocentesis and chorionic villus sampling for the confirmation of Down syndrome.

Down syndrome may be accompanied by some other health problems

Individuals suffering from Down syndrome are at risk of certain other health conditions. Congenital heart defects, infections of the ear, problems related to the eye and hearing are common issues that arise during infancy while there are some problems such as sleep apnea, thyroid disease, and early onset of Alzheimer’s disease which affect adulthood.

Every individual affected with Down syndrome is different, still, some features are common.

Some characteristic features related to Down syndrome which occur in each and every person affected by it include :

• Delayed growth and development

• Eyes, which are almond-shaped

• Degraded muscle tone

• Small hands and feet with shorter extremities

• Short height

• A flattened nasal bridge

• Short neck with shorter ears