methylation and epigenetics

Question 1

Neurofibromatosis 1 is an example of a

Answer 1

somatic mosaicism - not germline blood and germ cells negative for mutant allele

Question 2

Germline mosaicism would mean that

Answer 2

blood and sperm would be positive for mutant allele

Question 3

the mitochondrial genome is

Answer 3

maternally inherited, sperm mitochondrial DNA is ubiquitinated and degraded

Question 4

the mitochondrial heteroplasmy =

Answer 4

mitochondrial mosaicism

100% chance - ALL children are affected with varying sensitivity - and effects every part of the body

Question 5

In fragile X - pre-mutation stage results in / full mutation

Answer 5

increased mRNA production and less protein

leads to no mRNA no protein

Question 6

2 FMR1-related disorders with pre-mutation in fragile X

Answer 6

1- tremor ataxia syndrome (males>females)

2- premature ovarian insufficiency

Question 7

May get phenotypic variability with fragile X due to

Answer 7

methylation of CpG islands

Question 8

Anticipation

Answer 8

number of triplet repeats increases with each generation

fragile X - expansion in maternally inherited X