Brainscape's Knowledge GenomeTM

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


See full index

Genetics in Medicine > Genetics in Medicine 1-10 > Flashcards

Genetics in Medicine 1-10 Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

True or false: Single gene disorders have a high recurrence rate

A

True

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

True or false: Environmental diseases are less common than single gene disorders

A

False

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

What is a somatic mutation genetic disorder?

A

Mutation within a gene in a defined population of cells that results in disease, e.g. breast cancer

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

Are males or females affected more by autosomal dominant inheritance?

A

Equally affected

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

What types of proteins are normally affected by autosomal conditions, and name some conditions.

A

Structural proteins, receptors, transcription factors.

Myotonic dystrophy, Marfan syndomr, Huntington disease

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

What is the definition of penetrance?

A

The frequency with which a specific genotype is expressed by those that posses it, usually given as a percentage.

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

What is meant by expressivity?

A

The extent to which a heritable trit is manisfested by an individual - variation in expression.

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

What is the risk of offspring being affected in autosomal recessive inheritance to 2 carrier parents?

A

1/4

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

Name some conditions with autosomal recessive inheritance

A

CF
Metabolic disorders
Haemachromatosis
Sickle cell disease

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

Who is affected by X-linked inheritance?

A

Males, however cannot have male to male transmission

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

Name some conditions with X-linked inheritance

A

DMD
Fragile X
Red-green colour blindness
Haemophilia

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

What are some of the difficulties with using PCR?

A

Gene may be too big

GC-rich regions are difficult to PCR - fragile X mutation has repetitive CGG sequence

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

What genetic techniques are used if we already know the identity of the mutation? And if we do not?

A

PCR

DNA sequencing
Karyotyping

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

Which direction is DNA written in

A

5’ –> 3’

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

What is satellite DNA?

A

Large blocks of repetitive sequences, found at centromeres and heterochromatic chromosomal regions

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

What occurs in transcription and translation?

A

Transcription: DNA –> RNA
Translation: RNA –> protein

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

What is an intron?

A

Non-coding region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the difference between SNV and SNP mutations?

A 
SNV = variant, >1%
SNP = polymorphism, <1%
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are the definitions of aneuploidy, polyploidy and mosaicism?

A 
Anueploidy = gain or loss of chromosome
Polyploidy = gain entire sets of chromosomes
Mocaism = diploidy (normal 2 copies) and aneuploidy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is non-disjunction in meiosis?

A

Failure of chromosome / chromatid separation. Some gametes have no genetic material, others have double.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is Trisomy 21? Describe some of the clinical features observed.

A

Downs syndrome.

Upward slanting eyes, protruding tongue, single palmar crease, wide sandal gap, learning difficulties

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is trisomy 18? Descrive the clinical features observed.

A

Edwards Syndrome.
Microcephaly, low set ears, cleft palate, clenched hands, rockerbottom feet, severe mental retardation, organ malformations e.g. umbilical / inguinal hernia, heart/kidney/eye abnormalities

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is trisomy 13? Describe the clinical features.

A

Patau syndrome.

Small at birth, mental retardation, microcephaly, brain defects, cleft palate, heart defects, abnormal genitalia

24
Q

What are the sex chromosome disorders, 45X and 47XXY?

A 
45X = Turner's syndrome
47XXY = Klinefelter's syndrome
25
Q

Describe some features of Turner’s syndrome

A

Loss of ovarian function, no puberty, webbed neck, swollen hands and feet, coarctation of aorta, reduced IQ`

26
Q

Describe some features of Klinefelter’s syndrome

A

Testicular dysgenesis, 30-50% gynaecomastia, long limbs in adults

27
Q

What is a molar pregnancy?

A

Double paternal DNA with no maternal. “Conception without an embryo”

28
Q

Summarise which numerical abnormalities occur during:

1) meiosis
2) fertilisation
3) post-fertilisation

A

1_ gain/loss of single chromosome

2) gain of whole chromosome sets
3) gain or loss during mitosis

29
Q

What is a robertsonian translocation?

A

Whole arm of chromosome breaks off and fuses with another chromosome

30
Q

What is a chromosome inversion?

A

Chromosome broken at 2 points, then rejoined. Paricentric: occurs about centromere, pericentric: no centromere involvement

31
Q

What is FISH used for?

A

Copy number imbalance, aneuploidy, confimration of G-banding and array CGH, identifying specific abnormalities in cancer

32
Q

What is a copy number variation?

A

DNA segment with variable copy number compared with refernece genome.

33
Q

What is MLPA?

A

Mulitplex-ligation-dependent-probe-amplification.

Mulitplex PCR, alternative to FISH

34
Q

What is array CGH?

A

Genome wide screen which sees genomic imbalances at high resolutuion

35
Q

What are the advantages of array cGH?

A

early diagnosis
high reesolution
high accuracy
information on relevant genes

36
Q

What is a gatekeeper gene?

A

Cancer gene that monitors and controls cell division and death, preventing accumulation of mutations.

37
Q

What is a caretaker gene?

A

Cancer gene that improves genomic stability e.g. repair of mutations

38
Q

What is a landscape gene?

A

Cancer gene that controls the surrounding stroll environment

39
Q

What is a tumour suppressor gene? Name a well-known example.

A

Suppresses cell growth to protect cells from becoming cancerous. BRCA1/2.

40
Q

What is an oncogene?

A

Regulates cell growth and differentiation. Activation mutations allows cell growth to become out of control.

41
Q

What is Knudson’s two-hit hypothesis? Name the classic example of cancer that demonstrates this.

A

2 mutations are required within a single cell to cause cancer. However, in inherited disease, one of the mutations already exists, therefore there is a higher risk of cancer as only one further mutation is required.

Retinoblastoma

42
Q

Which inheritance patterns do most cancer syndromes follow?

A

Autosomal dominant

43
Q

Name some features that help to distinguish a familial cancer against a sporadic.

A

Familial = younger age of inset, FHx of same type / genetically related cancers

44
Q

What is HNPCC, what is its inheritance pattern and what does it hold a risk for?

A

Hereditary non-polyposis colorectal cancer. 60-80% risk of bowel adenoma, other cancer risks = endometrial/ovarian/stomach/ GUT. Autosomal dominant inheritance

45
Q

What criteria is used to assess whether someone has HNPCC?

A

Amsterdam

46
Q

What is Li Fraumeni Syndrome?

A

Mutation in P43 tumour supressor gene. 50% cancer by age 40 = breast, brain, adrenocortex, leukaemia.

47
Q

Inheritance of haemachromatosis

A

Autosomal recessive

48
Q

Term used to describe the extent to which a heritable trait is manifested by an individual

A

Expressivity

49
Q

Myotonic dystrophy is inherited in an autosomal _________ fashion

A

Dominant

50
Q

The classic Fragile X mutation occurs in a tract of sequence which is

A

Repetitive

51
Q

This drug blocks the abnormal tyrosine kinase activity in cases of chronic myeloid leukaemia which have the classic translocation between chromosomes 9 and 22.

A

Gleevec (Imatinib)

52
Q

The chromosome that carries the BCR/abl fusion gene is referred to as the _____________ chromosome

A

Philadelphia

53
Q

Mutations in this gene result in microcephaly

A

ASPM

54
Q

The condition of diabetes and deafness is ______________inherited

A

Maternally

55
Q

Small cell lung cancers which harbour EGFR/HER1 mutations can be treated with this drug.

A

Gefitinib

56
Q

OLA assay stands for?

A

Oligonucleotide ligation assay

57
Q

Term used to describe the process of random inactivation of one of the X chromosomes in cells with more than one X chromosome

A

Lyonisation

Genetics in Medicine (4 decks)

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