W31/L6: Prenatal testing

Question 1

What information can we get from 1st trimester combined screening?

Answer 1

T21

T18

Question 2

What information can we get from 2nd trimester screening?

Answer 2

T21
T18
Neural tube defect

Question 3

What are the components of 1st trimester screening?

Answer 3

Blood test at 10 weeks

US at 12 weeks

Question 4

What are the components of 2nd trimester screening?

Answer 4

Blood test at ~16 weeks

Question 5

What are the two modes of fetal cell sampling?

Answer 5

CVS

Amniocentesis

Question 6

At what age do we normally do CVS?

Answer 6

11 weeks

Question 7

At what age do we normally do amniocentesis?

Answer 7

15-16 weeks

Question 8

What’s the name of the rapid detection test for T21?

Answer 8

FISH

Fluorescence in situ hybridisation

Question 9

Why is classical analysis (karyotyping) slower to get results?

Answer 9

It requires dividing cells

Question 10

What’s the term for the short arm of a chromosome?

Answer 10

p (“petite”)

Question 11

What’s the term for the long arm of a chromosome?

Answer 11

q

Question 12

What’s an acrocentric chromosome?

Answer 12

One where the p arm is very small and contains little coding information

Question 13

What’s a Robertsonian translocation?

Answer 13

Translocation between two acrocentric chromosomes