The difference between ET and JAK2 ET…?

[Pachena]

I’m a little confused about these two. My SIL doesn’t have the JAK2 tho I do have it.

I don’t understand the differences between the two diagnoses 😊

I am 60 and my SIL is 42. She is on drugs as well for Ulcerative Colitis. They are anti rejection drugs. She was diagnosed with ET a year or 2 ago when she had a TIA while driving and was hospitalised for a week where she had a BMB and told she had ET. Her platelets were over 1 million. No JAK2 positive tho. She is on a high dose of Hydrea.

I was wondering if there is any difference between the two? JAK2 makes the cells multiply is that right, so wouldn’t there be some sort of multiplication going on with my SIL for her to have the ET?

I find the science a bit over my head. Can anyone dumb it down for me at all please ☺️

Thank you 🌸🌼🌸

[EPguy]

ET can be caused by any of three mutations, or even with none at all (triple negative)

The three for ET are: Jak2, CALR, and MPL, or if triple negative, no "driver" mutations at all. If your SIL has no Jak2, then most likely it's CALR, but the other two options are also possible.

PV is easier to figure here since it's almost always Jak2.

[Pachena in reply to EPguy]

thank you so much. She said she didn’t have any mutations, so I guess she is triple negative then. I had heard that expression on here tho now I know what it means. Thank you 🤩

[hunter5582]

As Epguy stated there are three different driver mutations that cause ET, JAK2, CALR, and MPL. There are also people with ET who are triple-negative. Just to make things more interesting, there are two primary types of the JAK2 mutation, JAK2v617f and JAK2 Exon 12. Even more interesting, there are other types of JAK2 mutation that have been detected, but they are even more rare and not commonly tested for. Note that there are different types f JAK2 tests that have different levels of sensitivity. MPN molecular biology is complex and interesting. It is worth learning more about.

Here is a very good presentation

youtube.com/watch?v=K5ZXdIw...(Not working as expected?)

[Orangeboykitty in reply to hunter5582]

Thanks Hunter! Very interesting presentation.

[Mishie14 in reply to hunter5582]

Fascinating to watch. One key learning for me is my ET journey started quite some time ago, not from a trigger or whatever DNA change that happened last year when JAK2 was detected. She is an excellent presenter. I appreciate having more info to add to my MPN references. Thank you hunter5582!

[Pachena in reply to hunter5582]

so very interesting Hunter 🤩 Thank you so much ✔️

[Ovidess]

Dr. N is a great teacher! Very helpful to my understanding of WHY ME?

[givingITMybest]

Wow, I found this enlightening. Thank you