The Genetic Basis of Disease

Question 1

What is a single nucleotide variant?

Answer 1

A difference in a single nucleotide

Question 2

What is a copy number variant?

Answer 2

An insertion, deletion, inversion or dublication of > 1000 nucleotides

Question 3

What are short tandem repeats?

Answer 3

Repetitive elements of recurring DNA motifs

Question 4

What are Indels?

Answer 4

Insertion or deletion polymorphisms

Question 5

What qualifies for a rare disease?

Answer 5

<1% mutation rate

Question 6

What do epigenetics do?

Answer 6

They affect both DNA and histones by modulating DNA and switching genome on and off due to environmental factors

Question 7

What is histone modification?

Answer 7

This is when epigenetic factors bind to histone tails and affect how tightly histones are wrapped round DNA which changes the availability of the genes to be activated.
If wrapped too tight then DNA inaccessible and if too loose then DNA very accessible

Question 8

Mendelien disease factors?

Answer 8

single gene, rare, high penetrance

Question 9

Complex disease factors?

Answer 9

Polygenic, common, variable penetrance (large environmental influence)