Week 5- Modes of Inheritance

Question 1

How many individual chromosomes do adults have and so how many pairs? How many of these are autosomal?

Answer 1

46 chromosomes
23 pairs of chromosomes
22 autosomal chromosomes

Question 2

How do we know if a disorder is autosomal dominant?

Answer 2

It manifests in heterozygotes

Question 3

What is the pedigree pattern of an autosomal disorder?

Answer 3

Vertical

Question 4

What is osteogenesis imperfecta? What type of inheritance pattern does it follow?

Answer 4

Mutation in the gene for collagen production leads to weaker bones. Autosomally dominant inheritance

Question 5

What is the pedigree pattern of an autosomal recessive disorder?

Answer 5

Horizontal

Question 6

What is the mode of inheritance for cystic fibrosis?

Answer 6

Autosomal recessive

Question 7

What is a X linked disorder?

Answer 7

Present on X chromosome so always affects males more (they only have one X chromosome), if the disorder is dominant and a father is affected all daughters will be

Question 8

What is mitochondrial inheritance?

Answer 8

The mutation is in mt DNA, so inherited only via mother and all children will be affected. Extent of illness will depend on how much mutated mitochondria is inherited and the severity of the mutation