Brainscape's Knowledge GenomeTM

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


See full index

MBD/MI (Wothaya) > Structural Chromosomal Abnormalities > Flashcards

Structural Chromosomal Abnormalities Flashcards

1
Q

What are some examples of structural abnormalities?

A 
Translocation
Inversion
Deletion
Duplication
Rings
Robertsonian
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the two types of translocational abnormalities?

A

Reciprocal and robertsonian

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

What is translocation?

A

Exchange of two segments between non homologous chromosomes

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

What is the main reason translocation takes place?

A

Inappropriate non-homologous end joining

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

What is non-homologous end joining?

A

DNA repair mechanism that repairs double stranded breaks by literally just sticking them back together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How is a derivative chromosome created?

A

Broken bits of chromosome being stuck back on the wrong chromosome

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

What is balanced translocation?

A

There is non-homologous end joining but because the net amount of DNA in a cell hasn’t changed, it doesnt matter

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

What is the philadelphia chromosome?

A

Derivative chromosome 22

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

What does the philadelphia chromosome cause?

A

The activation of the oncogene nature of the gene

Leads to types of leukaemia and myeloma

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

What is the philadelphia chromosome formed from?

A

Non-homologous end joining between a proto-onco gene on chromosome 9 and a gene on chromosome 22

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How are unbalanced individuals produced?

A

Tetravalent structure formed instead of a bivalent structure

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

What is a tetravalent structure formed from?

A

Two normal chromosomes and two chromosomes that have undergone inappropriate non-homologous end joining

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

What do unbalanced individuals cause?

A

Essentially trisomic for one end of the chromosome and monosomic at the other end

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

What are the results of unbalanced reciprocal translocation?

A

May lead to miscarriage
Learning difficulties/physical difficulties

Very person-specific so clinical features vary

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

Where is the only place robertsonian translocation can happen?

A

With acrocentric chromosomes that carry specific sets of copies of rRNA

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

What happens if you loose chromosomes in robertsonian translocation?

A

Nothing

17
Q

What is a robertsonian chromosome?

A

Two chromosomes that can stick together with a single centromere

18
Q

How many chromosomes does a balanced carrier have?

A

45

19
Q

What has happened if there are 46 chromosomes including a robertsonian?

A

Unbalanced carrier

20
Q

What are the products of normal mitosis, reciprocal and robersonian?

A

Normal - two bivalents
Reciprocal - quadrivalent
Robertsonian - trivalent

21
Q

What is a terminal deletion?

A

Loss of tetrameric chunks

22
Q

What is an interstitial deletion?

A

Loss of a chunk of chromosome in the middle of an arm

23
Q

What are some examples of interstitial deletions?

A

Prader-willi
Digeorge syndrome
Cri du chat

24
Q

What do deletions cause?

A

A region of monosomy

25
Q

How can we see gross deletions?

A

Metaphase spread on G-banded karyotype

26
Q

Why do deletion/duplication events generally happen?

A

Unequal crossing over

27
Q

What are the steps of chromosome staining?

A 
Blood sample taken
Add phytohaemagglutinin and culture medium
Culture at 37 deg celcius for 3 days
Add colchicine and hypotonic saline
Cells fixed
Spread cells onto slide by dropping
Digest with trypsin and stain with giemsa
Analyse and karyotype
28
Q

What are the steps in fluorescent in situ hybridisation (FISH)?

A 
Culture cells and metaphase spread
Add fluorescent probe
Denature probe and target DNA
Mix probe and target DNA
Probe binds to target
29
Q

What are the components of PCR?

A 
Template
Primers
Polymerase
Nucleotides
Buffer
MgCl2
30
Q

What is non-invasive prenatal testing?

A

Taking fetal DNA from maternal blood

MBD/MI (Wothaya) (57 decks)

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