Mendelian Inheritance Flashcards
What does a normal chromosome consist of?
Centromere
P arm
Q arm
What do mutations in genes do?
Alter the structure of the protein produced so change the function due to incorrect amino acid
What is an example of a disease associated mutation?
Sickle cell disorder
What kinds of inheritance does sickle cell disorder show?
Recessive
What is sickle cell disorder caused by?
Single mutation in one gene
What is a pedigree chart?
A family history that can show inheritance of mutations where:
Boys are shown as squares
Girls are shown as circles
Affected are coloured in
What are boys shown as in a pedigree chart?
Squares
What are girls shown as in a pedigree chart?
Circles
What are people who are affected shown as in a pedigree chart?
Coloured in
What can children be in a pedigree chart?
Unaffected
Carrier
Affected
What is used to determine the risk of a child inheriting a disorder?
Punnet square
What is recessive and what is dominant in a punnet square?
Lowercase is recessive
Uppercase is dominant
What can some kinds of recessive inheritance give?
A mild version of the disease (carrier shows mild symptoms)
What is cystic fibrosis caused by?
A single gene mutation
How many kinds of mutations cause cystic fibrosis?
3000
How many people are a carrier of cystic fibrosis in the UK?
1/25
How many people are affected by cystic fibrosis in the UK?
1/2500
What kind of disorder is cystic fibrosis?
Autosomal recessive
What kind of disorder is achondroplasia?
Autosomal dominant disorder
What is achondroplasia?
Autosomal dominant disorder where long bones are shortened due to a mutation
What do you see in a pedigree chart of autosomal dominance?
Each child has a 50/50 change of inheriting the mutation
No skipped generations
Equally transmitted by men and woman
What kind of disorder is Huntington’s disease?
Autosomal dominant
What is Huntington’s disease?
Autosomal dominant disorder that is neuro-degenerative
What are some genetic disorders that are not autosomal?
Sex linked (X linked)
What are properties of sex linked disorders?
Only males affected classically
Can skip generations
Unaffected woman and affected men can transmit the condition
No male to male transmission
What kind of disorder is Duchenne muscular dystrophy?
Sex linked disorder
Multiple genes in the same molecular pathway can cause what?
The same mendelian disease
What are examples of disorders caused by many genes?
Long QT
ARVC
Cardiomyopathy
