Brainscape's Knowledge GenomeTM

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


See full index

Techniques of Molecular Medicine > Genetic disorders > Flashcards

Genetic disorders Flashcards

1
Q

Define allele

A

Variant form of a gene in the same locus

Humans are diploid because they have two alleles at each genetic locus

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

Define genotype

A

Pair of alleles represents a genotype of a specific genes

Broadly, the genotype refers to the genetic makeup of an organism

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

Define homozygous

A

A genotype that features two identical alleles

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

Define heterozygous

A

A genotype that features two different alleles

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

Define phenotype

A

Composite of an organism’s observable characteristics or traits

Results from the expression or the interaction between an organism’s genotype and environmental factors

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

Define dominant

A

Allele that will be manifested in the phenotype of a heterozygote

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

Define recessive

A

Allele that won’t be manifested in the phenotype of a heterozygote, manigestation only results in homozygous individuals

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

Define mutation

A

Permanent alteration of the nucleotide sequence in the genome

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

Define wild type

A

An allele which is not mutated and codes the phenotype most common in a natural population

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

Define SNP

A

Mutation carried by more that 1% of the population

Leads to variations in the amino acid sequence

Also occur in noncoding regions of DNA

If SNPs occur in a gene, the gene is described to have more than one allele

Does not significantly affect the phenotype, so is not selected for and therefore survives in the population

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

Define mendelian disorder

A

Disorder controlled by a single locus in an inheritance pattern based on Mendel’s Law

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

Define genetic susceptibility

A

Increased likelihood of developing a particular disease based on a person’s genetic makeup

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

What information does DNA provide?

A

Information to understand how living organisms function

Study and treat disorders

Understand disease susceptibility

Study history and evolution

Make drugs

Understand and treat cancer

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

What is a genetic disorder caused by?

A

One or more abnormalities in the genome

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

TRUE or FALSE

All mutations are passed down

A

FALSE

Only if it occurs in the germline

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

Example of an autosomal dominant condition

A

Huntington’s

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

Example of an autosomal receissive condition

A

Cystic fibrosis

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

Example of a X-linked disorder

A

Haemophilia A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Example of a non disjunction condition

A

Trisomy 21

20
Q

Example of a condition caused by DNA deletion

A

Cri-du-chat

21
Q

What are the 4 types of genetic disorders?

A

Single gene

Chromosomal

Multifactorial

Somatic

22
Q

Types of chromosomal genetic disorders

A

Deletion

Duplication

Inversion

Translocation

Non disjunction

23
Q

Types of single gene genetic disorders

A

Autosomal dominant

Autosomal recessive

X-linked

24
Q

Pedigree of autosomal dominant conditions

A

Occurs in half of the offspring

25
Q

Pedigree of X-linked recessive

A

Men are affected

Women are carriers

For women to be affected, the mother must have both copies of the recessive allele

26
Q

Pedigree of a Y-linked dominant

A

Never occur in females

Occur in all male descendent of an affected male

27
Q

Pedigree of X-linked dominant

A

If mother have the disorder

Males and females have even chance of receiving conditions

If father has the disorder

Daughters will 100% get disorder

None of the sons have disorder

If both have the disorder

  • 100% of daughters will have disorder
  • 50% of sons will have disorder
28
Q

What is congenital afibrinogenemia?

A

Condition characterised by the lack of fibrinogen protein in the plasma

Leads to increase in coagulation times

29
Q

What is fibrinogen?

A

Plasma hexameric glycoprotein

30
Q

Which cells secrete fibrinogen?

A

Secreted mainly by hepatic parenchymal cells

31
Q

What is the role of fibrinogen?

A

Plays an important role in haemostatic balance and support for platelet aggregation

32
Q

What mutation leads to congenital afibrinogenemia?

A

Mutation to one of the 3 fibrinogen genes

FGA
FGB
FGG

33
Q

Describe the process behind polymerase chain reactions

A

Technique used to make copies of a specific DNA region in vitro

Goal = make enough target DNA region so that it can be used

34
Q

How is Tag polymerase specialised for PCR?

A

Isolated from Thermus aquaticus bacteria

It is very heat-stable

Most active around 70C

35
Q

What is required for Taq polymerase to carry out its function?

A

Primer

36
Q

What are primers?

A

Specific sequences of DNA

Bind via complementary base pairing

37
Q

What is gel electrophoresis?

A

Technique used to visualise PCR reactions

Fragments of DNA are pulled through a gel matrix by an electric current which separates DNA fragments according to size

Exploits the negative charge of DNA

DNA fragments of the same length form a band on the gel which can be stained with a DNA-binding dye

38
Q

Describe the process behind Sanger sequencing

A
  1. The DNA molecule is denatured
  2. The solution with a single stranded DNA is added to DNA primers, DNA polymerase, four type of dNTPs and ddNTPs
  3. ddNTPs bind (lack hydroxyl groups) and elongation is terminated
  4. So if a ddNTP binds to the first complementary codon on a strand = reveals the first codon of the DNA
39
Q

How do ddNTPs terminate sequence elongation?

A

Lack hydroxyl groups

Nucleotides without hydroxyl groups cannot create phosphodiester bonds with adjacent nucleotides

40
Q

How do ddNTPs tell which base it is bound to?

A

Colour coded

41
Q

What are types of point mutations?

A

Silent

Nonsense

Missense

42
Q

What are conservative point mutations?

A

Mutated protein’s function is not too different from that of the wildtype

Causes limited phenotypic expression

43
Q

What are non-conservative point mutations?

A

Do have a big effect on wild type since the protein expressed as a cause of the point mutation is very different from that of the wild type

44
Q

Mechanisms underlying point mutations

A

Substitution

Insertion

Deletion

Inversion

45
Q

Describe the nomenclature for describing point mutations

A

g.1749T>G

Gene 1749 T is replaced by G

On amino acid 45 cysteine is replaced by phenylalanine

Techniques of Molecular Medicine (12 decks)

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