Prenatal Testing/Genetics Prac

Question 1

When nuchal translucency measured? what is abnormal?

Answer 1

11-14 weeks

>3mm is abnormal

Question 2

Four 2nd semester screening analytes?

Answer 2

1. a-fetoprotein (AFP)
2. oestriol
3. hCG B-sub unit
4. inhibin A

Question 3

Four 2nd semester screening analytes, what suggests Trisomy 21?

Answer 3

decreased AFP and oestriol

increased hCG and Inhibin A

Question 4

2 analytes in 1st trimester measured?

Answer 4

hCG

PAPP-A

Question 5

decreased hCG and PAPP-A suggest?

Answer 5

Trisomy 18

Question 6

2 analytes in 1st trimester measured what is trisomy 21?

Answer 6

decreased PAPP-A and increased hCG

Question 7

final risk calculation for 1st semester screening includes?

Answer 7

maternal age
weight
gestation

Question 8

2 analytes in 1st trimester measured what is trisomy 18?

Answer 8

decreased hCG and PAPP-A

Question 9

2 camping technique to get fetal cells?

Answer 9

chorionic villus sampling

amniocentesis

Question 10

decreased PAPP-A and increased hCG suggest?

Answer 10

Trisomy 21

Question 11

risk of miscarriage for chorionic villus sampling

amniocentesis?

Answer 11

chorionic villus sampling: 1%

amniocentesis: 0.5 %

Question 12

Robertsonian translocation, which class of chromosomes?

Answer 12

acrocentric chromosomes

Question 13

What sequencing uses optical tag?

Answer 13

Illumina

single molecule real time - Pacific BioSci

Question 14

What sequencing uses bridge amplification?

Answer 14

illumina

Question 15

NIPT is?

Answer 15

Non-invasive prenatal testing

Question 16

Non-invasive prenatal testing use for screening only, why?

Answer 16

low positive predictive value
scope of test decreased
cell-free fetal DNA mostly from cytotrophoblast: maybe false positives