http://www.ncbi.nlm.nih.gov/books/NBK1194/

My students and I have done a fair bit of work on the basic science of the TTR amyloidoses, including a number of published papers.

Familial amyloid polyneuropathy (FAP) is usually associated with the L55P mutation (very aggressive) and sometimes the V30M (less aggressive) mutation in the TTR gene.

As the article says, FAP is an autosomal dominant condition which means that somebody only needs to inherit one copy of the mutant gene to get it. It is very uncommon, mainly affecting kindreds from Sweden and Portugal.

In practical terms, what this means is that somebody who is at risk of FAP will have a strong family history of it (sporadic amyloidogenic mutations in the TTR gene are extremely rare).

If there is no family history then there is nothing to worry about.

Thanks, Kiwi. My neuro will soon test me for it. I'm not too concerned that I have it, but my uncle and father are simultaneously exhibiting some issues that overlap, though no neuropathy I think. I just skimmed the article but will sit down and read it when I get a chance tomorrow. Given that you're working on this, perhaps I can ask you this in advance: how accurate will the genetic testing that my neuro will do be? Should I also push for a fat pad biopsy?

My own worry is that it could be Amyloidosis, but perhaps not familial. Thanks in advance.

Genetic screening for L55P or V30M is very easy and accurate to do. It would take my lab (we are not a commercial set-up) about a week. I wouldn't worry about a fat pad biopsy.

Neuropathy can be associated with amyloidogenic proteins other than TTR. The information in this link might give you something to think about and discuss with your neurologist; http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3531896/.

Thanks, Kiwi. I've read that among other things a few months ago when Amyloidosis was suspected. If I'm not mistaken, the piece I posted, which I'm now going to read in detail, notes many other mutations and not just those two, no? Is it that those two are the most common?

Yes, it can, and my main concern is primary, or even secondary (though to a lesser degree), but my neuro seems to think familial, I'm not sure quite why. We'll see.

Regarding the fat pad biopsy, why do you think I shouldn't concern myself with one? If you mean for familial, I understand, though I could have a mutation that has yet to be recorded. For the non-genetic ones, it's the surest way to diagnose, about 80% or higher precision, short of biopsying the organ itself.

Thanks again for your input and assistance.

"Regarding the fat pad biopsy, why do you think I shouldn't concern myself with one?"

Oops, my mistake - I don't know much about about amyloidosis from a clinical perspective.

After a bit more reading I agree with you that a fat pad biopsy would be a good plan.

Hi David,

Although I don't have any known family history my Neuro Doctor wants to test me for FAP. The test kit is from "Athena Diagnostics" and is sent to ones home. Then one can either take the kit to a Quest Diagnostics location (they own Athena) or they can send someone to your home to draw the blood. Here's a link to Athena's site; http://www.athenadiagnostics.com/ And here's an interesting article I found about Amyloid Neuropathies; http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3531896/

I'm not sure there's adequate evidence in my case to warrant testing but she seems to think it's worth it. I'm not sure if I will proceed or not.

Cliffman

Hi Cliffman,

Thank you for this. Much appreciated. I'm waiting to hear from him about where he wants to do the testing. Once I know that, I can proceed. If it's a quality place with thorough testing, then we'll just proceed. This is a good resource. I also appreciate the article, which is a good look at the subject as a whole.

I'll speak to my neuro when he does call. How about you: if you don't have to pay for it/if insurance covers it, why not do it? I think non familial forms are possible in my case, but I don't know.

Be well!
Dave

I tell ya David after reading about it I sure hope the test comes back negative! Yikes....

I have to find out if my insurance co. will cover it. Please let me know if you proceed in getting it done.

Thanks,
Cliffman

Hi David,

In my instance the insurance co. won't pay for it. They charge $1770.00 for the test at Athena or depending on one's income from the prior year it can be less. Given the cost I will pass.

I'm praying your results are negative if you decide to proceed.

Cliffman