Author: Morgan T
Editors: Yanxi Chen and He-Hanson Xuan
Artist: Lilian Chen
Down syndrome is one of the most common chromosomal disorders in the United States, with approximately 360 babies with Down syndrome born per day worldwide. Between 1979 and 2003, the prevalence of Down Syndrome increased by 30%.
People with Down Syndrome usually have similar physical features, but the effects on their daily life may differ. Some of their common facial characteristics include flattened and broad faces and narrowed eyes. With respect to effects on personal life, they tend to have lower IQ and learning difficulties. The biological reason behind this is still being researched; however, scientists have suggested that the potential decrease in intelligence may be caused by the lack of extended educational opportunities for long-term potential. As a lifelong disorder, genetics and external factors, such as environment and personal experience, are crucial to their cognitive abilities. Their average life expectancy is about 60 years, and it has been said that ethnicity may be one of the major factors; whether or not these people will have shorter life expectancies is still a myth and can vary in different individuals.
Down Syndrome is caused by DNA mutations in the sex cells, resulting in a condition known as nondisjunction. While normal haploid sex cells should contain 23 chromosomes, the 21st chromosomes of these haploid cells fail to segregate so the gamete produced would have 24 chromosomes This is also why Down Syndrome is also known as Trisomy 21, as there are 3 copies of the 21st chromosomes instead of 2. Down Syndrome mutation is also more likely to occur in the ovum (female sex cells) than the sperm (male sex cells). This explains how the chance of the incidents increases with the age of the mother – 1 in several thousand births from teenage mothers; 1 in a hundred from 40-year-old mothers.
Most children born with Down Syndrome have weaker muscles and intellectual disabilities, which require more effort to take care of them. To ensure adequate conditions to raise children with Down Syndrome, pregnant women are often offered diagnostic genetic testing, including blood tests and amniocentesis, which involves taking samples from the amniotic fluid surrounding the fetus in the uterus and looking at the number of chromosomes in the cells. Many countries have established laws and acts regarding abortion and general welfare for people with Down Syndrome. For example, in England, Wales, and Scotland of the United Kingdom, the 24-week time limit on having an abortion allows parents to decide whether they want to take the risk if the child suffers from physical or mental disabilities caused by Down Syndrome. The Down Syndrome Act 2022 in the same country also provides an opportunity to improve the living conditions of people with Down syndrome, which encourages the general public to learn more and be aware of the special needs of these people.
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