Week 10 - Chromosomal Abnormalities

Question 1

Define aneuploidy.

Answer 1

Loss or gain of whole chromosomes

Question 2

What is the chromosomal abnormality in Down’s syndrome?

Answer 2

Trisomy 21

Question 3

What is the chromosomal abnormality in Edward’s syndrome?

Answer 3

Trisomy, +18

Question 4

What is the chromosomal abnormality in Patau syndrome?

Answer 4

Trisomy, +13

Question 5

What is the only monosomy syndrome to be viable? Why?

Answer 5

Turner’s syndrome (45, X)

Phenomenon of X inactivation

Question 6

Which gender does Turner’s syndrome occur in?

Answer 6

Females

Question 7

List the key clinical features of Down’s syndrome.

Answer 7

1. Hypotonia
2. Characteristic facial features
3. Intellectual disability
4. Heart defects
5. Increased prevalence of leukaemia
6. Increased incidence of early Alzheimer’s