Genetics

Question 1

Monogenic traits

Answer 1

phenoypes created by the action of one gene.

Very few phenotypes are affected by one gene but many diseases arise from single gene mutations

Question 2

Euchromatin

Answer 2

non-condensed U can Use it.

Question 3

How do we reconcile alleleic differences in medicine when so many alleles exisit?

Answer 3

If the function of the two genes is basically the same, even if there are molecular alleleic differences we consider them functionally homozygous.

Question 4

How can we in medicine work around enzyme deficiencies?

Answer 4

We can use pharmacology to help mitigate the effects of certain deficiencies. Change the enzymes around the defective one.

Question 5

How do you explain dominant and recessive traits using the principle of dosage?

Answer 5

If you have a situation where an enzyme deficiency leads to a disease state and you loose one allele that codes for that enzyme, but the other alleleic variant you posses is capable of performing its function well enough that no observable functional defect is seen in the individual, this is a recessive trait (both need to be defective for an observable phenotype). Conversely if KO the single allele leads to an observable phenotype or disease state this is a dominant disorder.

Question 6

You have a dominant genetic disorder for polydactaly but for some reason you don’t have any extra digits; why? Your sister has a sixth finger but it’s more of a numb; how come?

Answer 6

although the disease is dominant the penetrance is low so it doesn’t manifest as often as you might expect.

your sister has penetrane (yes/no proposition) but the expressivity is low.

Question 7

co vs incomplete dominance

Answer 7

co-dominant with color, both show through

incomplete dominance- blending