Non-medelian inheritance

Question 1

Balance b/w genetics and environment

Answer 1

Varies. Some diseases are almost totally genetic, others mostly environment, others in b/w. Combos of education, health care, exposure, stress, genome, ancestor origin, etc.

Question 2

Temporal bias

Answer 2

Some traits may have conferred a beneficial effect in the past, now it might not be.

Question 3

GWAS

Answer 3

Genome-wide association study. Massive DNA analysis of huge number of people. Look for variations that are associated with a disease. Even still, some people experience it and others don’t even tho they share genetics.

Question 4

Mitochondrial disease

Answer 4

Only inherited from mother. Variable penetrance and expressivity. Ex. deafness, parkinsons, cardiomyopathy, others.

Question 5

Mitochondrial genome

Answer 5

16kb. 37 genes (other mitochondrial proteins are from the nucleus btw)

Question 6

Segregation of mitochondrial genome

Answer 6

mother with mild symptoms (ie some mito infected, some not). Depending how many get passed to child can affect severity.

Question 7

Example of organ functions from mito disease

Answer 7

Muscle (fatigue, weak), brain problems, diabetes, etc etc. Varied. Can be very hard to pin down. Lots of biochem testing, can take years.

Question 8

Epigenetics defined

Answer 8

Study of epigenetic inheritance, a set of reversible heritable changes in gene function or other cell phenotype with no change in DNA sequence. Changes may be induced spontaneously, in response to environmental factors, or in response to the presence of a particular allele, even if it is absent from subsequent generations. Reversible is key word.

Question 9

Examples of epigenetic diseases

Answer 9

Rett syndrome, Fragile X, Cancer (hyper or hypo methylated), Prader Willi disorder, Angleman disorder

Question 10

Prader willi syndrome

Answer 10

Active parental gene (SNRPN) not active. Results in low muscle tone as child. Grow up to be insatiably hungry, morbidly obese, blond, etc. Results from deletion, two maternal copies, or problem with methylation.

Question 11

Cancer and epigenetics. Example of colorectal cancer

Answer 11

Low folate intake results in DNA hypomethylation (lead to faulty gene expression; relocation and instability)and faulty DNA synthesis.

Question 12

Is methylation pattern inheritable?

Answer 12

Yes! Study in Sweden of good food supply and mortality of grandchildren. Smoking and stress could be others

Question 13

How do you combine risks to provide good info?

Answer 13

Don’t know! Hard to combine increased risks and decreased risks.

Question 14

Implications of epigenetics and disease

Answer 14

Can affect what you are prone to, how you will respond to disease or treatment