Patterns of inheritance

Question 1

What is epigenetics?

Answer 1

Something that effects gene expression and is inherited by daughter cells but not the result of changes to the DNA sequences
Controlled by the chromatin structure rather than by nucleotide sequence

Question 2

What is X inactivation?

Answer 2

Heterochomatin formation that occurs in female mammals which one X is randomly inactivated and only one is expressed

Question 3

What is a barr body?

Answer 3

A darkly staining, heterochromatic inactive X chromosome

Question 4

When does X inactivation occur?

Answer 4

During early embryogenesis - maintained colonaly in every subsequent cell division

Question 5

What happens to Tsix when Xist in increased when and X is picked to be active?

Answer 5

It spreads a coat over the DNA because it can no longer bind with Xist

Question 6

Why is the PAR area on the X and Y not inactivated?

Answer 6

So they can locate each other for appropriate segregation

Question 7

If an X chromosome lacks the XIC locus:

Answer 7

It cannot be inactivated because it does not have the Xist

Necessary

Question 8

If a XIC is translocated onto to an autosome:

Answer 8

The autosome is inactivated

Sufficiency

Question 9

What is dependent for phenotype in calico cats?

Answer 9

Epigenetic

Question 10

What is the naming convention for Klinefelers syndrome?

Answer 10

47, XXY

Question 11

How can a male escape X inactivation?

Answer 11

By having an extra X

Question 12

What is Retts syndrome?

Answer 12

Carry one normal and one defective MeCP2 (inactive) where the target is brain development, learning and memory (BDLM) in girls and boys die
Recessive X-linked disorder

Question 13

What does paternal imprinting mean?

Answer 13

An allele inherited from the father is not expressed in the offspring

Question 14

What does maternal imprinting mean?

Answer 14

An allele inherited from the mother is not expressed in offspring

Question 15

What does it mean when a locus is imprinted?

Answer 15

One allele is expressed and on allele is silenced in a parent-of-origin manner

Question 16

On the maternal chromosome, the ICR is bound to the CTCF protein and the H19 area is unmethylated. How does the enhancer do and what does it cause?

Answer 16

The enhancer binds to H19 leaving IgF2 inactive

Question 17

On the paternal chromosome the ICR and H19 are methylated. What does the enhancer do and what does it cause?

Answer 17

The enhancer binds to IgF2 making it active

Question 18

What is the father’s goal in breeding?

Answer 18

Get as many genes out in the world as possible regardless of the mother’s well being, growing strong babies

Question 19

The mother’s goal is:

Answer 19

To conserve her resources equally in its offspring while still being able to manage caring for them so growth should be limited

Question 20

If a mutated IgF2 is inherited from the father:

Answer 20

There is stunted growth

Question 21

If a mutated IgF2 is inherited from the mother:

Answer 21

Growth is normal

Question 22

What is Beckworth-Wiedmann’s syndrome?

Answer 22

Overgrowth and increased susceptibility to kid cancer
Disrupted genes of chromosome 11
Biallelic expression of IgF2 and no H19 expression
Pareternal uniparental disomy

Question 23

Paternal inheritance of a deletion of the specific region in Prader-Willi syndrome is also known as:

Answer 23

Maternal uniparental disomy

Question 24

Maternal inheritance of a deletion of the specific region in Angelman syndrome is also known as:

Answer 24

Paternal uniparental disomy

Question 25

Autosomal dominant:

Answer 25

Each effected individual has an affected parent
Males and females are equally affected
1/2 offspring of affected individual are also affected
Normal siblings develop normal babies

Question 26

Autosomal recessive:

Answer 26

Non-affected parents have a an affected babeh