The causes and effects of Down syndrome Some people wonder what Down syndrome is. How it is caused and how it is treated. The causes and effects of Down syndrome are due to the presence of an extra 21St chromosome. Effects include some birth defects and health problems. The physical characteristics are different from those of a person without Down syndrome. What is Down syndrome? It is a chromosomal disease caused by an error in cell division resulting in an extra 21st chromosome (scab). Down syndrome causes problems with a person's physical growth that vary based on severity. This disease can develop before or after the birth of a child. Fewer than 1,000 pregnancies for mothers under age 30 result in a child with Down syndrome. For mothers age 44, approximately 1 in 35 pregnancies results in a baby with Down syndrome (Crust). The only way to have a baby with Down syndrome is determined by the mother's age. 75-80% of children with Down syndrome are born to younger mothers. It is believed that a younger woman usually has more children than an older woman (Scab). What causes Down syndrome? A Robertsonian translocation occurs when part of chromosome 21 breaks off during cell division and attaches to another chromosome (usually chromosome 14) (Crust). There are 46 chromosomes in the body. 23 come from the mother and 23 from the father. When there is another copy or half a copy of chromosome 21, you will have a child with Down syndrome. The most common type of Down syndrome is trisomy 21. It is where the body has 47 chromosomes instead of 46 (Crust). Trisomy 21 is caused by a problem in cell division called nondisjunction; leaves a sperm or egg cell with an extra copy of chromosome 21. 95% of Down syndrome...... middle of paper...... chromosome. Most pregnancies of mothers aged 40 or older will have a higher risk of having a child with Down syndrome. The older the mother, the greater the chance that her baby will be diagnosed with Down syndrome. The effects of Down syndrome are ear infections, leukemia at an early age, different physical characteristics than a person without the syndrome, and birth defects. There are things that help a person deal with the disease by going to therapy and learning things to help their physical abilities. Works Cited Crosta, Peter. “What is Down syndrome?”. 2004-2014. Network. 30 April 2014. “Down Syndrome”. 2012. Network. April 30, 2014. "Facts about Down syndrome." November 6, 2013. Web. May 5. 2014.Kingsley, Jason. “Count on us”. Orlando, Florida: Harcourt + Brace & Company, 1994. Print.Laney, Dawn. “Down Syndrome”. Farmington City, MI: Greenhouse Press, 2003. Print.