Tay Sachs Disease, Gaucher Disease, Neiman-Pick Lysosomal Storage Disease Disorders

ERRATA: There is hepatosplenomegaly in Gaucher and Neiman-Pick, but there is NOT in Tay-Sachs. I also misspelled Hexosaminidase A in the powerpoint slide.

Sphigolipids are an important part of the cell membrane. However, when these lipids are improperly metabolized due to genetic disorders they build up in the lysosome causing problems. The collection of these diseases are called Sphigolipidosis, or Lysosomal Storage Diseases. If untreated these diseases can be lethal, but individuals often live long lives with proper enzyme replacement.We already covered I-Cell Disease, one example of a Lysosomal Storage Disease, in a previous section.

Tay-Sachs, Gaucher & Neiman-Pick are all Autosomal Recessive deficiencies of enzymes which are involved in the degradation of sphigolipids. When an enzyme in this pathway is deficient, the substrate for the enzyme builds up and causes problems. All 3 of these diseases are more common among Ashkenazi (Eastern European) Jews.

It can be tough to differentiate between different sphigolipidosis based solely on clinical presentation, because there is overlap in symptoms between the diseases. Thankfully the test writers usually aren't that evil. Most questions on this topic will be very straight forward. You are probably going to see something like "It is this disease. Which enzyme is deficient?" or "This substrate is building up. What disease is it?", but you might see a question that includes a clinical scenario so here are the basics.

Now that you are finished with this video you should check out the last video in the Biochem section here (http://www.stomponstep1.com/where-is-the-rest-of-the-biochemistry-section/)

Pictures Used:

This work is a derivative of "Outline Man Runner Cartoon Sprint Running" available at http://pixabay.com/en/outline-man-runner-cartoon-sprint-34669/ under Creative Commons 1.0 Public Domain Dedication
This work is a derivative of "Football Helmet" by Simanek available at http://openclipart.org/detail/86827/football-helmet-by-simanek under Public Domain Dedication

9 comentarios:

Stomp On Step 1
Stomp On Step 1:
Z Viqas, you are absolutely correct! That is a mistake. Tay-Sachs does NOT have hepatosplenomegaly. I added a note to the video and I am about to update the text and pictures on the website and video description. Thank you so much for pointing it out! I can't fix stuff if people don't take the time to let me know there is a problem so I really appreciate it
shir maor
shir maor:
Thank you so much! It really helped - the mnemonic for gaucher, maybe I missed, but do you have anything? (I just though of GGG or something)
bakary jatta
bakary jatta:
Useful lecture videos. Very much grateful and thumbs up to the producer for his sheer gesture in helping out students better prepare for USMLE.
Monica Alejandra Gonzalez Moreno
Monica Alejandra Gonzalez Moreno:
Thanks! you are great ! thanks for your enormous help!
Jay Snad
Jay Snad:
good job man, very helpful.
Manuel G Amezcua
Manuel G Amezcua:
I´d also point out that the name of the enzyme deficient in Tay-Sachs disease is Hexosaminidase, not Hexominidase; trivial, I know :P Also, thumbs up for the incredible effort you put in reviewing material for the yield scoring, making and editing of these videos.
Tay Sachs has no hepatosplenomegaly  thats the difference form the other 2.This fact needs to be corrected
Jeff Riddle
Jeff Riddle:
5,000 views and 3 people support with a comment.
Matute Family
Matute Family:
Thanks so mucho. It videos are very interesting¡
please give us more suggestions about biochemistry  high yield.