Mutations and genetic analysis Flashcards Preview

Principles of disease JK > Mutations and genetic analysis > Flashcards

Flashcards in Mutations and genetic analysis Deck (33):
1

3 types of chromosomal abnormalities

Numerical
Structural
Mutational

2

When is there a high incidence of mutation in pregnancy

First trimester with trisomy

3

Mostly maternal non disjunction syndromes - trisomy

Patau - extra 13
Edwards - extra 18
Down - extra 21
Klinefeller - XXY

4

Monosomy

Turners have one X

5

Downs syndrome

Advancing maternal age and problem with non disjunction
Facial dysmorphologies, 50-60 years and alzheimers

6

Patau syndrome

5% die in first month and due to non disjunction

7

Edwards syndrome

Developmental problems

8

Turners syndrome

Short females with neck webbing and wide spaced nipples who are infertile
Normal intelligence and lifespan

9

Klinefeler Syndrom

Gynaecomastia and are tall with long limbs and small testes with mild learning difficulties

10

Balanced

All genetic information still present but just in the wrong place

11

Robertsonian translocation

fuse 2 acrocentric chromosomes can lead to downs syndrome

12

Reciprocal translocation

Partial monosomy or trisomy

13

Paracentric inversion

Not too harmful

14

Pericentric inversion

Include centromere

15

Transition point mutation

Purine=> purine
Pyrimidine => pyrimidine

16

Transversion point mutation

purine<=> pyrimidine

17

PCR requirements

Heat tolerant Tac polymerase and polymerase
Sequence information and DNA
Oligonucleotide primers
Nucleotide

18

Name some uses of PCR

DNA cloning
In vitro mutagenesis
Forensic medicine
Gene identification for mutations

19

Name the 3 consecutive temperatures for denaturing, annealing and extending the DNA

93-95
50-70
70-75

20

Gel electrophoresis

Separate compounds on size and density
Apply electric field over agarose gel and negative DNA ==> positive electrode

21

What are some advantages of PCR

Fast, easy to use, sensitive and robust

22

ARMS

Like PCR but a different primer used to detect single base mutations and deletions

23

In ARMS explain the link between wild type allele and primer

Normal = Amplified
Mutant = not amplified

24

In ARMS explain the link between mutant allele and primer

Normal primer = no amplification
Mutant primer = amplification

25

Advantages of ARMS

Cheap and no label needed

26

State some slight drawbacks of ARMS

Electrophoresis also needed and the primer design is critical

27

State the disadvantages of ARMS

Need sequence information
Limited amplification size
Limited amounts of product
Infidelity of DNA replication

28

Restriction endonuclease

Enzyme used in RFLP from bacterial cell that always cuts DNA at the same sight by recognising specific parts of DNA and degrades DNA of incoming virus
Protective mechanism

29

Explain some positives/negatives of RFLP

Simple cheap and non radioactive
When electrophoresis is not always feasible

30

DNA sequencing

Precise order of nucleotide

31

ddNTP's

Chain elongating inhibitors of DNA polymerase

32

Some negatives/positives of DNA sequencing

Gold standard
Extensive equipment required and has poor quality read ( 70-900) bases

33

What do you base the decision on which mutation detecting method is used?

Sensitivity and specifity