Estimating Risk of Inherited Genetic Diseases Flashcards
(36 cards)
Define fitness
The ability of organisms to survive (long enough) to pass on their genes
How do neural alleles affect fitness?
Don’t at all
How do deleterious alleles affect fitness?
Sometimes decrease
How do advantageous alleles affect fitness?
Rarely increase
Name recessive diseases
Sickle cell and Thalassaemia
What can mutations in dominant and X-linked genes arise?
Inherited or de novo (new)
When are De Node mutations common?
In dominant disorders especially were disease reduces reproductive fitness - 1/3 Lethal X-L diseases
alleles in people with genotypes: 400AA + 150Aa + 100aa
A - 950
a - 350
total = 1300
Frequency of A (p) + Frequency of a (f) = ?
1
How to determine frequency of allele frequency?
Sum of type of allele (A or a) divided by number of total alleles (A+a)
How to determine frequency of genotype?
Number of people for genotype (AA/Aa/aa) divided by number of people
What is the ratio in terms of p and q for a punnet square of genotypes Aa and Aa?
AA : Aa : aa = p2 : 2pq : q2
What is the constant relative frequency?
p : q
What is the allele frequency for A from punnet square?
2p2+2pq
What is the allele frequency for a from punnet square?
2q2+2pq
Do dominant conditions become more common at the expense of recessive ones?
No
What are two principle of HWE?
- Allele frequencies remain constant between generations
- Relative proportion of genotypic frequencies remain constant between generations
What will the allele frequency be no matter what in HWE?
1
Should mutation in ignored in an ideal population?
Yes
Should migration occur in ideal population?
No so that there is no gene flow
Should mating be random in an ideal population?
Yes
Should there be a selective pressure in an ideal population?
No
Should the population be big or small in an ideal population?
Large
In ideal population, are allele frequencies equal or unequal in the sexes?
Equal
