Genetics #1 Flashcards
(12 cards)
1
Q
How are most mutations corrected?
A
-By DNA repair mechanisms in the cell (or eliminated)
2
Q
What do biochemical events lead to?
A
-Accidental errors in duplication, rearrangement, or deletion of parts of the genetic code.
3
Q
Hereditary mutation
A
- Present in the DNA of all body cells
- Copied every time body cells divide
4
Q
What is genetic disease?
A
5
Q
Main types of genetic mutations?
A
- Single gene
- Autosomal
- Sex-linked
- Alterations in chromosome number or structure.
6
Q
What is a single gene disorder?
A
- Condition caused by a mutation in a singe gene in one or both copies of the gene.
- May be present on an autosome or sex-linked chromosome (X)
7
Q
What is Marfan syndrome?
A
- A single gene disorder.
- defect in connective tissue= Affects various structures (eg. skeletal and cardiovascular)
8
Q
What is an autosomal disorder?
A
- Caused by a mutation in alleles on the autosomes.
-Most are recessive
(need two mutated alleles to be affected) - Each child of a recessive carrier parent has a 25% Chance of inheriting
9
Q
What is Phenylketonuria?
A
- Autosomal recessive
- Metabolic disorder caused by high levels of phenylalanine that are toxic to the brain
- Can cause brain damage
10
Q
What are Autosomal Dominant disorders?
A
- Only need 1 mutated allele to have the disorder
- Each child with affected parent has 50% chance of inheriting
- Affects either sex of offspring
11
Q
What is Huntington’s disease?
A
- Degenerative brain disorder
- Caused involuntary movements, nervous system deterioration and death.
- symptoms before 40yrs old
12
Q
Symptoms of Huntington’s Disease?
A
-Clumsiness, depression, memory loss, loss of muscle co-ordination and ability to speak.
