Many individuals with metabolic diseases are normal at birth but show symptoms shortly thereafter. Why?


An end to heart disease? Not quite. A new class of cholesterol lowering drugs called PCSK9 inhibitors (Links to an external site.)Links to an external site. is really good at lowering LDL levels, but evidence of how well it reduces the mortality of heart disease is not so clear. From this New York Times article, discuss the problems treating a complex disease like heart disease. Find information about familial hypercholesterolemia and what different treatment options would be available, considering that seven different genes are known to contribute to this disease (OMIM 143890 (Links to an external site.)Links to an external site.).  In your post, explain or summarize why the new drug Repatha is so powerful in reducing LDL cholesterol, and then pick one of the genes from OMIM (see the Phenotype-Gene Relationship table) and discuss one cause of hypercholesterolemia and possible treatment option, based on the gene you picked.

Bio Peer Response: 4/5/19 100 min

A new LDL drug was endorsed and the researchers had very high expectations and were rooting for the end of heart disease. With a following study of this new drug conducted to patients, it had simliar benefits like a statin. For patients who don’t mind or do mind the high price of this drug, it has been suggested to wait for long-term results when more and more people start to use it. The problems of this disease is that they “are not related to statins at all…[you’ll need a] doctor to determine what’s really causing [the] symptoms. And some people tolerate one statin better then another.” (Krumholz, H., 2017) This drug is so powerful in treating heart disease because typically dozes of this medication is 90 mg/dl (this is considered low) and using Repatha is 30 mg/dl. 

“Familial hypercholesterolemia is an autosomal dominant disorder characterized by elevation of serum cholesterol bound to low density lipoprotein (LDL), which promotes deeposition of cholesteral in the skin, tendons, and coronary arteries (Hobbs et al.. 1992, OMIM)” This can happen in both homozygous and heterzygous. Houlston, R. et al. 1988, all discovered that that patients coronary artery disease have a high level of LDL concentration in contrast of those who don’t have coronary artery disease. This suggests “that [LDL] measurements may help predict the risk of coronary heart disease in individuals with familial hypercholesterolemia.” Treatment for this is chaning lifestyle like exercising and consuming a “healthy low-fat diet”.

RESCOURCES:

https://www.nytimes.com/2017/03/20/health/ldl-cholesterol-heart-disease-drugs-pcsk9-inhibitors.html?rref=collection%2Fsectioncollection%2Fscience&action=click&contentCollection=science&region=stream&module=stream_unit&version=latest&contentPlacement=4&pgtype=sectionfront (Links to an external site.)Links to an external site.

https://www.omim.org/entry/143890 (Links to an external site.)Links to an external site.

https://www.mayoclinic.org/diseases-conditions/familial-hypercholesterolemia/diagnosis-treatment/drc-20353757 (Links to an external site.)

Bio Questions: 4/4/19
1. Many individuals with metabolic diseases are normal at birth but show symptoms shortly thereafter. Why?

2. List the ways in which a metabolic block can have phenotypic effects.

3. If phenylalanine was not an essential amino acid, would diet therapy (the elimination of phenylalanine from the diet) for PKU work? Do not just say yes or no. Give a short explanation.

4. Describe the quaternary structure of the blood protein hemoglobin.

5. Transcriptional regulators are proteins that bind to promoters (the 5’ flanking regions of genes) to regulate their transcription. Assume that a particular transcription regulator normally promotes transcription of gene X, a transport protein. If a mutation makes this regulator gene nonfunctional, would the resulting phenotype be similar to a mutation in the gene X itself? Why or why not?