1 / 15

Down Syndrome

Down Syndrome. Sayed Zeeshan Alvi Premed 3. What is it?. Down syndrome, also known as Trisomy 21, is a genetic disorder that presents complications in a persons physical and mental capabilities. History. During ancient times, infants with disabilities were either abandoned or killed.

symona
Download Presentation

Down Syndrome

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Down Syndrome • Sayed Zeeshan Alvi • Premed 3

  2. What is it? • Down syndrome, also known as Trisomy 21, is a genetic disorder that presents complications in a persons physical and mental capabilities.

  3. History • During ancient times, infants with disabilities were either abandoned or killed. • Doctor John Langdon Down was the first to describe the characteristics of Down syndrome in a published report in 1866. • By the 20th century, Down syndrome was formally recognized as a mental disability.

  4. Causes

  5. Genetics • Trisomy 21 • Translocation

  6. Trisomy 21 • AKA 47,XX,+21 for females and 47,XY,+21 for males • caused by a failure of the 21st chromosome to separate during gamete formation. • Results in having an extra chromosome present in either egg or sperm(24 chromosomes). • Final zygote has 47 chromosomes, 3 being chromosome 21, thus Trisomy 21 • 88% of cases of trisomy 21 result from non separation of the chromosomes in the mother, 8% from non-separation in the father, and 3% after the egg and sperm have merged • In mosaic Down syndrome 1 to 2.5% of cases, some of the cells in the body are normal and others have trisomy 21

  7. Translocation • Extra chromosome 21 occurs due to a Robertsonian translocation (2–4% chance). • The long arm of chromosome 21 is attached to another chromosome, often chromosome 14. • Can occur as a new mutation or hereditary

  8. Signs

  9. Complications • Heart: congenital heart disease in newborns with Down syndrome is around 40%. • Hearing and Vision:Vision problems occur in 38 to 80%. Between 20 and 50% have strabismus, in which the two eyes do not move together. Cataracts occur in 15%, and may be present at birth. • Neurological: Individuals with Down syndrome have mild (IQ: 50–70) or moderate (IQ: 35–50) intellectual disability with some cases having severe (IQ: 20–35) difficulties. • Fertility: Males with Down syndrome usually do not father children, females have lower rates of fertility relative those who are unaffected. Fertility is estimated to be present in 30–50% of women.

  10. Epidemiology • Down syndrome occurs in about 1 per 1000 births and results in about 17,000 deaths. • Maternal age affects the chances of having a pregnancy with Down syndrome. At age 20 the chance is 1 in 1441; at age 30 it is 1 in 959; at age 40 it is 1 in 84; and at age 50 it is 1 in 44

  11. Management • Screen for Diseases • Hearing Aid • Speech Therapy • Sign Language • Monitor heart (electrocardiogram and ultrasound of the heart) • Physical Therapy • Tonsillectomy(prevent sleep apnea)

  12. Sources • http://en.wikipedia.org/wiki/Down_syndrome • http://www.ndss.org/ • http://www.gizmodo.com.au/2013/07/scientists-may-have-found-a-genomic-off-switch-for-downs-syndrome/ • http://www.larasig.com/sites/larasig.com/files/images/trisomy21_0.jpg

  13. Thank You

More Related