Brainscape's Knowledge GenomeTM

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


See full index

0. Foundations of Medicine > Chromosome Mutations + Abnormalities > Flashcards

Chromosome Mutations + Abnormalities Flashcards

1
Q

<p>What are the three different types of chromosomal abnormalities?</p>

A

<p>Numerical, structural, mutational</p>

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

<p>What is the result of non-disjunction?</p>

A

<p>Two gametes with disomy (meiosis 1)</p>

<p>1 gamete with disomy - (meiosis 2)</p>

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

<p>What is trisomy 21 known as?</p>

A

<p>Down's Syndrome</p>

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

<p>What is trisomy?</p>

A

<p>The addition of an extra chromosome</p>

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

<p>What is responsible for 50% of first trimester miscarriages?</p>

A

<p>Trisomy mutations</p>

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

<p>What are the features of someone with down's syndrome?</p>

A

<p>Characteristic facial dysmorphologies

IQ less than 50

Average life expectancy (50-60 years)

Alzheimer’s disease in later life</p>

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

<p>What is trisomy 13 known as?</p>

A

<p>Patau syndrome Incidence: 1 in 5000

Multiple dysmorphic features and mental retardation</p>

<p>About 5% die within first month, very few survive beyond first year

Non-dysjunction (90%), maternal origin

Unbalanced Robertsonian translocation (10%)</p>

<p></p>

<p></p>

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

<p>What is Trisomy 18 known as?</p>

A

<p>(Edwards syndrome) Incidence: 1 in 3000 Severe developmental problems; most patients die within first year, many within first month</p>

<p>Non-disjunction (90%), maternal origin</p>

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

<p>What is 45, X mutation known as?</p>

A

<p>Turner syndrome Incidence: 1 in 5000 to 1 in 10000 (liveborn)

Incidence at conception much greater, about 97% result in spontaneous loss</p>

<p>Females of short stature and infertile Neck webbing and widely spaced nipples
Intelligence and lifespan is normal

Female because there is no Y chromosome</p>

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

<p>What is 47,XXY mutation known as?</p>

A

<p>(Klinefelter syndrome)Incidence: 1 in 1000
Tall stature, long limbs

Male but infertile, small testes, about 50% gynaecomastia

Mild learning difficulties</p>

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

<p>What are the terms used to describe complete or incomplete retention of DNA during a mutation?</p>

A

<p>Balanced or unbalanced</p>

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

<p>What is the definition of a balanced translocation?</p>

A

<p>There is still a complete set of DNA between the two chromosomes, if the translocation takes place in a non-critical location, there will be no major effects to the individual</p>

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

<p>What is meant by reciprocal translocation?</p>

A

<p>Involving breaks in two chromosomes with formation of two new derivative chromosomes</p>

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

<p>What are the different types of Structural abnormalities?</p>

A

<p>Deletions

Insertions

Inversions

Translocations</p>

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

<p>What is the effect of unbalanced translocation on the gametes produced?</p>

A

<p>Production of gametes with, partial trisomy and partial monosomy, this will result in offspring with abnormal phenotypes</p>

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

<p>What are accrocentric chromosomes?</p>

A

<p>One of the arms of the chromosome is very short</p>

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

<p>What is robertsonian translocation?</p>

A

<p>When the two longer arms of accrocentric chromosomes combine, the short arms are lost and also fuse together</p>

18
Q

<p>What does Robertsonian translocation result in</p>

A

<p>Balanced - normal gametes</p>

<p>Unbalanced - Trisomy and Monosomy</p>

19
Q

<p>What is pericentric inversion?</p>

A

<p>When the inversion takes place over the centromere</p>

20
Q

<p>What is polymorphism?</p>

A

<p>The natural genetic variation within a populaiton</p>

21
Q

<p>What are the different types of genetic mutations?</p>

A

<p>Germline or somatic</p>

<p>Gene disruption /disease-associated</p>

<p>Polymorphism</p>

22
Q

<p>What are the types of non-coding mutations?</p>

A

<p>Coding mutations -</p>

<p>Silent – synonymous e.g. CGA (Arg) to CGC (Arg) (GIVES THE SAME AMINO ACID)</p>

<p>Missense (A MISSENCE MUTATION IS A POINT MUTATION WHICH A SINGLE NUCLEOTIDE CHANGE RESULTS IN A CODON THAT CODES FOR A DIFFERENT AMINO ACID)</p>

<p>Nonsense (CODON FOR AMINO ACID IS CHANGED TO A CODON THAT CODES FOR A CHAIN TERMINATING CODON)</p>

<p>Frameshift – deletion / insertion</p>

23
Q

<p>What are transitions - point mutations?</p>

A

<p>Purine to purine or pyrimidine to pyrimidine</p>

24
Q

<p>What are transversions?</p>

A

<p>Purine to pyrimidine or vice versa</p>

25
Q

<p>Learn Mutation Nomenclature</p>

A

<p>.</p>

26
Q

<p>What do we use to detect mutations?</p>

A

<p>Polymerase chain reaction (PCR)</p>

<p>Gel electrophoresis</p>

<p>Restriction fragment length polymorphism (RFLP) analysis Amplification refractory mutation system (ARMS)</p>

<p>DNA sequencing</p>

27
Q

<p>What do we need for PCR?</p>

A

<p>Sequence information</p>

<p>Oligonucleotide primers</p>

<p>DNA Nucleotides</p>

<p>DNA polymerase</p>

28
Q

<p>What are the three stages of PCR?</p>

A

<p>Denaturation - 93-95 degrees celcius</p>

<p>Anneal - 50-70 93-95 degrees celcius</p>

<p>Extend 70-75 93-95 degrees celcius</p>

29
Q

<p>Why is taq polymerase used?</p>

A

<p>Heat resistant</p>

30
Q

<p>What is used to separate DNA fragments?</p>

A

<p>Gel electrophoresis</p>

31
Q

<p>What is the charge of DNA?</p>

A

<p>Negatively charged</p>

32
Q

<p>What does Gel Electrophoresis allow?</p>

A

<p>Visualisation of DNA fragments</p>

33
Q

<p>What are the advantages of Gel Electrophoresis</p>

A

<p>Speed

Ease of use

Sensitive

Robust</p>

34
Q

<p>What are the PCR applications?</p>

A

<p>DNA cloning</p>

<p>DNA sequencing</p>

<p>In vitro mutagenesis</p>

<p>Gene identification</p>

<p>Gene expression studies</p>

<p>Forensic medicine</p>

<p>Typing genetic markers</p>

<p>Detection of mutations</p>

35
Q

<p>What are the advantages of Amplification Refractory Mutation System?</p>

A

<p>Cheap</p>

<p>Labelling not required</p>

<p>Primer design critical</p>

36
Q

<p>What is the principle of theAmplification Refractory Mutation System?</p>

A

<p>Specific primers anneal to sample DNA</p>

<p>If a mutant primer is used and amplification occurs then the presence of a mutant allele can be conformed</p>

<p></p>

<p>If a normal normal primer is used and amplifiacation occurs then the presence of a wild type allele can be confirmed</p>

37
Q

<p>What are the disadvantages of Gel electrophoresis?</p>

A

<p>Need sequence information</p>

<p>Limited amplification size</p>

<p>Limited amounts of product</p>

<p>Infidelity of DNA replication</p>

38
Q

<p>What is the action of endonuclases?</p>

A

<p>Recognise specific DNA sequences</p>

<p>Always cut DNA at the same site</p>

39
Q

<p>How are endonucleases used to detect mutations?</p>

A

<p>They cut the DNA at a portion of mutated nucleotide sequence - cutting of the DNA strand only occurs at mutated site, length of travel on the gel therefore gives indication of mutation</p>

<p>Two bands gives indication of a carrier</p>

40
Q

<p>What are the Advantages / disadvantages of restriction endonucleases?</p>

A

<p>Simple Cheap</p>

<p>Non-radioactive</p>

<p>Requires gel electrophoresis</p>

<p>Not always feasible</p>

41
Q

<p>What is used for DNA sequencing?</p>

A

<p>Chain terminatino method , sanger sequencing, dideoxynucleotides are used</p>

42
Q

<p>What is the Advantages / limitations of DNA sequencing?</p>

A

<p>Gold standard for mutation detection</p>

<p>Automation and high throughput</p>

<p>Expensive equipment</p>

<p>Poor quality sequence read (First part of sequence (15 to 40 bases) Deterioration after 700-900 bases)</p>

<p>Next generation sequencing 18 billion bp in 4 days (about 6 human genomes)</p>

0. Foundations of Medicine (167 decks)

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