Pedigree Analysis Flashcards
1
Q
What is a pedigree?
A
A family tree that tracks one particular phenotype, helping to work out the genotype - likelihood of disease in offspring
2
Q
Why do we use a pedigree tree ?
A
- For the study of human genetics
- Can’t do control crosses in humans
- Looks at families instead or even entire populations
- Can be done with other organisms
3
Q
Simple definition of pedigree
A
An orderly presentation of family information
4
Q
The 5 patterns of inheritance
A
- Autosomal Recessive
- Autosomal Dominant
- X-linked Dominant
- Y-linked Recessive
- Y-linked Inheritance
5
Q
Autosomal Recessive Traits
A
- For rare traits most affected individuals have unaffected parents
- All offspring of 2 affected individuals are affected
- Expressed in males and females equally
- In rare traits, unaffected parents with affected offspring may be related to each other
6
Q
Albinism
A
The inability to produce melanin, regardless of ethnic skin colour.
= issues with skin cancer & vision
7
Q
Sickle cell anaemia
A
- Characterised by RBC in the shape of a crescent moon or sickle
- These RBC do not carry oxygen as effectively
- Sickle cells can also damage capillaries
- Associated with attacks and anaemia
8
Q
How is sickle cell anaemia a autosomal recessive trait ?
A
- Hb is an oxygen transport molecule in red blood cells
- Sickle cell Hb is abnormal and causes RBCs to become crescent or sickle shaped
