tanisha
Forum Senior
Topics: 5
Posts: 121
|
Its a area of intense research.
I just came across a question in qbank,so it sounds to be high yield topic.
It was about the mutations in LDL receptor gene.
What i understand is(i am just trying to make it simple)
The gene for LDL receptor is having 5 general domains & 18 exons.
There are >200 mutations.
Though i came across 5 classes of mutations.
Class 1
decreased transcription of LDL receptor gene
which involves signal sequence near exon 1.
class 2
defect
in dissociation of LDL from receptor in endosome.Trouble being
initially transported to golgi complex & can become trapped in ER.
defect in exon 7 to 14
class 3
reduced binding of LDL
defect near exon 2 to 6
But i am little confused for class 4 & class 5.
Can anybody tell me?
Also can anybody verify the above information.
Edited by tanisha on 06/18/05 - 10:14 PM
|
| tanisha
Forum Senior
Topics: 5
Posts: 121
|
Do anybody know?
or can tell me?
|
| ssrpk
Forum Fanatic
Topics: 154
Posts: 2,798
|
- The gene for the LDL receptor, which is autosomal dominant, is located on the short arm of chromosome 19.
- Since its discovery by Goldstein and Brown, more than 420 different mutations have been identified that have a meaningful impact on receptor function.
- LDL receptor function ranges from completely absent to approximately 25% of normal receptor activity.
- The 5 classes of mutations are as follows:
- Class 1 includes absent receptor proteins.
- Class 2a includes a complete blockade in the transport of the receptor between the endoplasmic reticulum and the Golgi apparatus.
- Class 2b includes a partial blockade in the transport of the receptor between the endoplasmic reticulum and the Golgi apparatus.
- Class 3 involves an inability of the receptor to bind LDL normally.
- Class 4 involves an inability to accumulate in clathrin-coated pits after binding the LDL. This prevents internalization.
- Class 5 exhibits an inability to release LDL to the interior of the cell after internalization. This prevents the recycling of the receptor back to the cell surface.
___________________
life is guud
|
| ssrpk
Forum Fanatic
Topics: 154
Posts: 2,798
|
http://www.emedicine.com/med/topic1072.htm
___________________
life is guud
|
| tanisha
Forum Senior
Topics: 5
Posts: 121
|
thank you ssrpk
|
|
| |
| | | | | |
