Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MCP Unit 2 > Lecture 9: Prenatal Genetics > Flashcards

Lecture 9: Prenatal Genetics Flashcards

1
Q

Is the recurrence risk for open neural tube defect high or low? why?

A

high

multifactorial; gene + env

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is MSAFP dnd what is an abnormality an indication for?

A

maternal serum alphafetoprotein
high/low –> fetal abnormalities
prenatal diagnosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the most common aneuploidy and autosomal aneupolidy in spontaneous abortion?

A

45,X (95% will terminate spontaneously)

Trisomy 16

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the non-invasive tests for prenatal genetics?

A

examination
ultrasound
Testing Maternal AFP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the invasive tests for prenatal genetics?

A 
cytogenics
biochemical
molecular studies
Testing fetal AFP
Amniocentesis
CVS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Why are some prenatal tests considered invasive?

A

needle inserted to collect fetal cells, tissues, or fluids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What does nuchal translucency on an ultrasound indicate?

A

possible xs abormality

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What fetal anomalies can ultrasounds detect?

A

nuchal translucency, clefting, neural tube defects (NTD)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Where is AFP produced, and what is the test sensitive to?

A

produced in fetal liver, found in mother’s serum

test is sensitive to mother’s WEIGHT, race, diabetic status

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What do high/low level of AFP indicate?

A 
Low = down syndrome; xs anomaly
High = NTD
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

is AFP used for diagnosis?

A

No - risk assessment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What method is used to detect Down Syndrome?

A

Maternal Serum Quad Test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

If a lab cannot determine nuchal translucency as a screen for Down Syndrome, what tests can they offer?

A

PAPP-A + Maternal Serum Quad Test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is NIPS(/NIPT)?

A

Non-Invasive Prenatal Screening(/Testing)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How and when is NIPS performed?

A

use cfpDNA (cell free placental) at 10-22 weeks
then sequence
use precise software to analyze aneuploidies present

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

After NIPS, how would diagnosis be performed?

A

Karyotype analysis

FISH on amniotic fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Which is more accurate: NIPS or serum screening?

A

NIPS

18
Q

What is amniocentesis? When is it performed?

A

Needle goes into amniotic cavity, draws amniotic fluid
16-18 weeks
early: 13/14 weeks

19
Q

Which is more risky - early or later amniocentesis? Why?

A

early is riskier

not as much amniotic fluid - could remove too much –> loss of mobility of fetus –> developmental defects

20
Q

What tests can be performed after amniocentesis?

A

AFAFP (like MFAFP)
Cytogenetics
Metabolic Assays
Molecular diagnostics

21
Q

what must be know for AFAFP/MFAFP testing?

A

gestational age

known standards for comparison

22
Q

What are low AFP levels indicative of?

A

Trisomies 13, 18, 21
Mosaic Turner Syndrome
Tiploidy
Unbalanced translocations

23
Q

What are high levels of AFP indicative of?

A 
teratoma
renal obstruction/agenesis
uropathy
upper GI obstruction
bladder/cloacal exstrophy
24
Q

What are reasonable explanations for increased AFP levels??

A

gestational age incorrectly reported
mom’s weigh nigh/low
twins

25
Q

How is high AFAFP confirmed?

A

Ach test
Ach is only found in neural tube
If it is found in amniotic fluid, it must have escaped through a defect

26
Q

How is low AFAFP confirmed?

A

Karyotype analysis

27
Q

What is a risk of CVS?

A

limb reduction

28
Q

What studies cannot be performed with CVS?

A

AFP studies - no fluid collected

29
Q

What studies are performed with CVS?

A

cytogenics
metabolic assays on cells
molecular diagnostics

30
Q

What does CVS test? What does it not test?

A

Placenta

NOT fetal tissue

31
Q

How must abnormal CVS results be confirmed?

A

amniocentesis

32
Q

What type of mosaicism gives the most accurate CVS findings?

A

Complete - found in both fetus and placenta

33
Q

Why can CVS be advantageous?

A

can be performed in first trimester - can abort sooner

34
Q

what is non-directive genetic counseling?

A

family decides

35
Q

What is intracytoplasmic sperm insertion (ICSI) and when is it used?

A

single sperm injected into egg

low sperm count

36
Q

What is in vitro fertilization? How does implantation then occur?

A

fertilization in petri dish
embryos are tested
appropriate ones undergo zygote intrafallopian transfer (ZIFT)

37
Q

When is polar body analysis useful?

A

determining which IVF embryo to implant
both parents are carriers
if polar body has mutation, oocyte doesn’t

38
Q

What is Preimplantation Genetic Diagnosis?

A

8-cell stage: one cell tested by FISH

interpret xs composition

39
Q

Why can’t karyotype analysis not an option with Preimplantation Genetic Diagnosis?

A

no metaphase cell

40
Q

What type of egg donor technology can be used for a woman who has a mitochondrial defect?

A

swap nucleii

have most of bio mom’s genes; don’t have mito defect

MCP Unit 2 (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions