Down Syndrome

Question 1

Down syndrome is the most common

Answer 1

chromosomal disorder

Question 2

Aneuploidy

Answer 2

having an abnormal # of chromosomes

Question 3

down syndrome is a genetic form of

Answer 3

Anueploidy

Question 4

likely hood of down syndrome occurrence related to

Answer 4

maternal age

Question 5

95% of all cases of down syndrome caused by

Answer 5

nondisjuction or an error in cell division during meiosis resulting in trisomy of chromosome 21

Question 6

2 ideas proposed for the likely hood of down syndrome related to maternal age

Answer 6

• mothers oocytes may change as a result of aging process (become less viable unlikely for success) (women are born with all oocytes they will ever have)
• as mothers age increases likely hood of being exposed to damaging environment agents such as (drugs, chemicals, radiation)

Question 7

some physical manifestations of down syndrome

Answer 7

• growth failure (shorter)
• small square head with distinguishing facial features: flat facial profile, small nose w depressed nasal bridges & upward slanting eyes with epicantral folds
• tend to have fat base at nape of neck
• ALSO have accompanying heart defects

Question 8

some cognitive changes of down syndrome

Answer 8

some degree of mental retardation, may include impulsive behavior, poor judgement, short attention span & delayed learning

Question 9

only current way to accurately determine presence of DS in fetus

Answer 9

• through chromosome analysis

- invasive chorionic villus sampling, amniocentesis or percutaneous umbilical blood sampling

Question 10

Prenatal screening & diagnoses

Answer 10

-most commonly used are blood tests that measure maternal serum levels of a-fetoprotien, human chronic gonadotropin (hCG), unconjugated estriol, inhibin A and pregnacny associated plasma portien A. Results of 3 or 4 tests together with maternal age used to determine probablity of pregnant women getting