{"id":696,"date":"2020-01-25T23:16:05","date_gmt":"2020-01-26T05:16:05","guid":{"rendered":"https:\/\/americanpregnancy.org\/?p=696"},"modified":"2021-12-09T13:37:00","modified_gmt":"2021-12-09T19:37:00","slug":"down-syndrome","status":"publish","type":"post","link":"https:\/\/americanpregnancy.org\/healthy-pregnancy\/birth-defects\/down-syndrome\/","title":{"rendered":"Down Syndrome: Trisomy 21"},"content":{"rendered":"
Down syndrome is a genetic disorder<\/a> caused when abnormal cell division results in an extra full or partial copy of chromosome 21. This extra genetic material causes the developmental changes and physical features of Down syndrome.<\/p>\n Down syndrome varies in severity among individuals, causing lifelong intellectual disability and developmental delays. It’s the most common genetic chromosomal disorder and cause of learning disabilities in children. In the United States, Down syndrome occurs in 1 of every 800 infants with many as 6,000 children born with Down syndrome each year. It is estimated that about 85% of infants with Down syndrome survive one year and 50% of those will live longer than 50 years. According to the National Down Syndrome Society, there are more than 350,000 people living with Down syndrome in the United States.<\/p>\n A better understanding of Down syndrome and early interventions can greatly increase the quality of life for children and adults with this disorder and help them live fulfilling lives.<\/p>\n Down syndrome can be caused by one of three types of abnormal cell division involving chromosome 21. For couples who have had one child with Down syndrome due to translocation trisomy 21, there may be an increased likelihood of Down syndrome in future pregnancies. This is because one of the parents may be a balanced carrier of the translocation.<\/p>\n The chance of passing the translocation depends on the sex of the parent who carries the rearranged chromosome 21. If the father is the carrier, the risk is about 3 percent, with the mother as the carrier, the risk is about 12 percent.<\/p>\n In all cases of Down syndrome, but especially in cases with translocation trisomy 21, it is important for the parents to have genetic counseling in order to determine their risk. There are no known behavioral or environmental causes of Down syndrome.<\/p>\n Some parents have a greater risk of having a baby with Down syndrome, including:<\/p>\n As a woman\u2019s eggs age, there is a higher risk of the chromosomes dividing incorrectly. Therefore the risk of Down syndrome increases with a woman\u2019s age.<\/p>\nWhat causes Down Syndrome?<\/h3>\n
\nThe three genetic variations include:<\/strong><\/p>\n\n
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What is the Risk for Down Syndrome?<\/h3>\n
Maternal Age<\/h4>\n