I have ET and Jak2 - I notice that a lot of posts mention CalR what is this? Will it be mentioned on my blood results? should I ask my consultant about it?
I know you guys will know so thanks as evefr for the support and the information.
Look after yourselves
Cassandra
Hi Cassandra.
Some people with ET (or MF) carry the CalR mutation. The three mutations that are associated with ET are Jak2; CalR ; and MPL.
I believe you have been diagnosed with the Jak2 mutation?
Also, there are ET patients who are ‘triple negative’, which just means they have none of the identified mutations, but may have a mutation which has not yet been identified.
Hi Cassandra - CALR is another type of genetic mutation , like JAK2, that can cause ET.
If you already have confirmation of JAK2 it’s highly unlikely you would also have CALR, so I doubt if they will test for it and it’s certainly not part of routine blood results.
As JAK2 is the most common mutation in ET patients they tend to test for that first and then the other mutations only if JAK2 comes up negative.
Hi, I’m ET Calr.
You have a Jak2 mutated gene I have a Calr mutated gene. Some people have both. Some people have more. I doubt very much you will have it as you have already been tested for mutations.
Some people don’t have mutations but other factors contribute to them being diagnosed with an MPN.
MPNvoice.org.uk is a wealth of simplified information.
Do not hesitate to ask questions on this forum. There are many people who will share their knowledge with you.
Equally so many people will be glad you have asked about things they also wanted to know about.
CALR = Calreticulin gene. One of the MPN driver mutations. It affects the JAK-STAT pathway in a different way than the JAK2 mutation, but has a similar impact. It is very rare to have both the JAK2 and CALR mutation, but it does happen. Whether your doc tested for it depends on what panel was ordered. Some panels are JAK2 only. Others test for a whole range of MPN driver and other relevant mutations. You will have to ask your doc.
Hey Cassandra... 
As others have already mentioned above, CALR is just one of the Three (3) classic 'Driver' mutations that are believed to a major cause of the blood cell proliferation abnormality that exists in all MPN conditions.
Here is a Link, that does explain it more fully:
mpn-mate.com/mpns-what-are-...
Hope this helps a tad...
Stay safe & well...
Steve
Hello Cassandra61, this article in one of our previous MPNLife newsletters will explain about the CALR mutation and how it was discovered.
mpnvoice.org.uk/documents/n...
There are also some very interesting articles about the other gene mutations that might help you understand more about them and what they mean.
mpnvoice.org.uk/documents/n...
mpnvoice.org.uk/documents/n...
best wishes, Maz
Just saw MPN Specialist | ET+CALR 
ET with CALR+ type 2
Have ET but not the hallmark genes, Jak2, CalR, etc...
