How does having an extra copy of chromosome 21 affect development?

Mar 27, 2023 ... There is no clear cause of the genetic condition, although maternal age is a major risk factor for Down syndrome. Women who become pregnant at ... Down syndrome is a condition that is caused by extra genetic material. It's one of the most common genetic conditions in the United States. The extra genetic ... Down syndrome is the most frequently occurring chromosomal disorder and the leading cause of intellectual and developmental delay in the US and in the world. Nov 6, 2024 ... Strabismus - Between 20% and 60% of those with Down syndrome have eyes that are not straight (strabismus). Esotropia (eyes that drift inward ... Aug 5, 2015 ... Down syndrome (DS) is a complex, highly variable disorder that arises from trisomy of chromosome 21. It was one of the first chromosomal ... Down syndrome signs and symptoms. A child with Down syndrome might take longer than other children their age to reach certain milestones and to develop certain ... Many children with Down's syndrome have some degree of hearing loss. Often this is caused by glue ear (a build-up of fluid in the middle ear) but there can be ... Aug 8, 2023 ... Down syndrome (trisomy 21) is a genetic disorder caused by the presence of all or a portion of a third chromosome 21. Summary · Down syndrome is a common genetic condition caused by an extra chromosome 21. · Every person with Down syndrome is an individual. · People with Down ... The additional partial or full copy of the 21st chromosome which causes Down syndrome can originate from either the father or the mother. Approximately 5% of ...