Down Syndrome By: Colleen Hybl
Chromosomal Abnormalities • 3 Types of Down Syndrome, but all of them occur on the 21st chromosome as an extra chromosome. 1. Trisomy 21: An entire extra chromosome 21 in all cells, so each one has 47 chromosomes in each body cell. 2. Translocation: The extra 21st chromosome material takes the place of part of another chromosome. 3. Moscaicism: An extra whole chromosome is present, but only in some of their cells. • Not inherited, but it is genetic
Symptoms/Characteristics Characteristics Problems/Complications Thyroid problems Vision Muscle & bone Joint Ear, nose, & throat Epilepsy Heart defects Susceptible to respiratory infection Mental Retardation (when the extra chromosome is placed in disturbs the brain cells) Prone to develop Leukemia & Alzhemier’s disease Most are sexually underdeveloped & sterile • Eyes that slant upward & outward • Narrow eye slit • Flattened face • Small head compare to body • Broad feet & short toes • Small ears & set low on head • Short arms & legs compare to body • Broad hands with short fingers and single palm crease • Small mouth that will cause the tongue to stick out • poor muscle tone
Population Index • This genetic disorder affects 1 out of 700 people. • 95% of the cases are Trisomy 21. • 4% of the cases are Translocation. • 1% of the cases are Moscicism. • The chances of a baby having Down Syndrome increases as the mother gets older the reason for this correlation is unclear.
Works Cited Bowman-Kruhm, Mary, Ed.D. Everything You Need to Know About: Down Syndrome. New York: The Rosen Publishing Group, Inc., 2000 Campbell, Neil A. AP* Edition: Biology Eighth Edition. San Francisco: Pearson Benjamin Cummings.2008 Conclusion Down Syndrome is a genetic disorder that is cause by an extra chromosome on the 21st chromosome. Even if child is born with Down Syndrome they can still leave lives that are similar or the same as children without Down Syndrome, like graduate and have a career. Conclusion/Works Cited