Inheritance Patterns Flashcards

1
Q

How are males represented in a pedigree drawing?

A

Squares

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

How are females represented in a pedigree drawing?

A

Circle

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

How are siblings represented in a pedigree drawing?

A

Line above them

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

How are partners represented in a pedigree drawing?

A

Line between them

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

How are affected people represented in a pedigree drawing?

A

Shaded in

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

How are carriers represented in a pedigree drawing?

A

Dots in their shape

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

How are children represented in a pedigree drawing?

A

Line down

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

How are consanguineous partners represented in a pedigree drawing?

A

Double line

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

What does SB mean in a pedigree drawing?

A

Still born

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

How are people of unknown sex represented in a pedigree drawing?

A

Diamond

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

How are miscarriages represented in a pedigree drawing?

A

Triangle

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

How is an abortion represented in a pedigree drawing?

A

Triangle with a line through

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

How are foetus’ of unknown sex represented in a pedigree drawing?

A

Diamond with a P inside

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

How are identical twins represented in a pedigree drawing?

A

Horizontal line between two diagonal lines

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

How are non-identical twins represented in a pedigree drawing?

A

Two diagonal lines

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

What is penetrance?

A

The percentage of individuals that carry the mutation and develop symptoms of the disorder

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

Give some characteristics of autosomal dominant inheritance

A
  • most affected individuals have an affected parent

- both sexes equally likely to inherit the allele

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

What is the risk for each child of an affected parent in autosomal dominant inheritance?

A

1/2

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

Can unaffected siblings of an affected individual pass the mutation on in autosomal dominant inheritance?

A

No

20
Q

What are obligate carriers?

A

Individuals that have the disease causing genotype but haven’t developed the disease

21
Q

What is variable expressivity?

A

Variation in the severity or symptoms of disorder between individuals with the same mutation

22
Q

What is somatic mosaicism?

A

When a new mutation arises at an early stage in embryogenesis

23
Q

What does somatic mosaicism mean for the cells of the individual?

A

The mutation will only be present in some tissues/ cells

24
Q

What is germ-line/gonadal mosaicism?

A

When a new mutation arises during oogenesis or spermatogenesis

25
Q

What does germ-line/gonadal mosaicism mean for the individual?

A

The mutation is present in a variable proportion of gametes and can be transmitted to the offspring

26
Q

What does anticipation mean in autosomal dominant inheritance?

A

Worsening of disease severity in successive generations

27
Q

When does anticipation characteristically occur?

A

In triplet repeat disorders

28
Q

Give some characteristics of autosomal recessive inheritance

A
  • may be due to consanguinity
  • usually one generation is affected
  • both sexes are affected and its transmissible between sexes
29
Q

Are heterozygotes affected by autosomal recessive inheritance?

A

No

30
Q

What genotypes are affected by autosomal recessive inheritance?

A

Homozygous and compound heterozygous

31
Q

What does compound heterozygous mean?

A

Two different mutations on the same gene which basically causes homozygosity

32
Q

What is the recurrence risk for a sibling of an affected person in autosomal recessive disease?

A

1/4

33
Q

What is the carrier risk for a sibling of an affected person in autosomal recessive disease?

A

2/3

34
Q

What does it mean for males and females if an X-linked trait is recessive?

A

Males can only be hemizygous but females can be homozygous or heterozygous

35
Q

What does it mean for males and females if an X-linked trait is recessive?

A

Women are unaffected carriers and there is no male -> male transmission

36
Q

What does it mean for males and females if an X-linked trait is dominant?

A

Women are affected and males are more severely affected and could be lethal

37
Q

What is the likelihood a child of a carrier female will inherit the X-Linked mutant allele?

A

50%

38
Q

What is skewed X-Inactivation?

A

Generally random but roughly 10% of women have it

39
Q

What is a manifesting carrier of an X-linked condition?

A

When a women has some symptoms in X-linked recessive conditions even if they’re heterozygous

40
Q

What is another term for Y linked inheritance?

A

Holandric

41
Q

How is holandric inheritance passed on?

A

Father -> son

42
Q

What are the two types of insertion and deletion?

A

Inframe or frameshift

43
Q

What is an inframe insertion or deletion?

A

When the indel is divisible by a multiple of 3

44
Q

What is a frameshift insertion or deletion?

A

Not a multiple of three

45
Q

Is an inframe or frameshift indel more likely to be disease causing?

A

Frameshift