3. Type of Genetic Disorder
Down syndrome is caused by a single gene, aka the one mutation in the 21st gene. (Being a chromosomal diseases) It is a trisomy and it is caused by a chromosomal disorder caused by an error in cell division that results in an extra 21st chromosome (ending up as 3). Specifics- It mutates through nondisjunction, the most common and called "trisomy 21", where theres an extra copy of chromosome 21 in every individual cell; and translocation, where there's only an extra part on chromosome 21. The third and final type, Mosaicism, is when some but not all of the cells have the extra chromosome, resulting in fewer negative effects/ symptoms.
4. Symptoms
External: poor/ decreased, short neck with excessive skin on the back of it, fattened facial profile and nose, smaller head, smaller ears, smaller mouth, upward slanting eyes with a skinfold that covers the interior of it.
Interior: impulsive behavior, poor judgment, short attention span, slow learning capabilities, minimal mental capacity, congenital heart defects, obesity, sleep apnea (interrupted breathing during sleep).
Interior: impulsive behavior, poor judgment, short attention span, slow learning capabilities, minimal mental capacity, congenital heart defects, obesity, sleep apnea (interrupted breathing during sleep).