D101 and D102 genes

[Wired123]

Is this a simple blood test that can be taken to identify the genes or is it something more complicated?

Going to speak to my private endo about doing these and hoping my insurance will pay.

[helvella Administrator Thyroid UK]

For clarity, the gene that affects T4 to T3 conversion is called DIO2 - that is, three letters and a number. Not D102 - a letter and three numbers. Not DI02 - two letters and two numbers.

The name comes from the enzyme that this gene affects which is a deiodinase. It removes an iodine atom from a thyroid hormone molecule - it deiodinates it.

On this forum we probably understand, but if you wish to look it up anywhere, it might help to get it right. If you are discussing with a doctor, and get it wrong, you are providing an excuse for them to dismiss what you say.

(More strictly, two single-nucleotide polymorphisms (SNPs) on the DIO2 gene, rs225014 and rs225015.)

academic.oup.com/jcem/artic...

The Wiki article provides a basic introduction as to what a single-nucleotide polymorphism (SNP) is and why it can be important:

en.wikipedia.org/wiki/Singl...

I suspect the test is more likely a saliva test than a blood test. At least one is a "buccal swab" - which is from the mouth.

[Hibs1 in reply to helvella]

yes was a saliva test

[Wired123 in reply to helvella]

Is this a test private hospitals do and insurance companies pay for? I’m insured and would want my Endo to do it as I’m already paying a fortune for insurance as it is!

I’ve checked with The Doctors Laboratory (TDL), a large testing company based off Harley Street and they actually don’t offer the test which is odd.

I checked with a large Private hospital in london and they also don’t offer the test despite having a large Endo dept.

I know the online companies do the test but is it reliable if large private hospitals in London don’t offer it?

[helvella Administrator Thyroid UK in reply to Wired123]

Afraid I have no idea if an insurer would do it.

I'd not have much an issue with any UK lab - provided it is appropriately licensed.

I don't think many standard pathology laboratories are involved with DNA sequencing. It is its own specialism! I wouldn't be surprised if labs get other labs to do this sort of test (if they see the need to offer it at all).

[Wired123 in reply to helvella]

Even if a lab or hospital does not carry out a test, there’s nothing to stop things being sent on. My partner had some blood drawn at the private wing of an NHS hospital in central London last year. Basic tests were done in house and results available in minutes! The more complex genetic tests required the blood to be sent off to a specialist lab at Oxford University.

So the logistics and process are there if a reliable lab is available. If there was such a lab then surely they would be running around signing agreements with hospitals and Endos offering the testing service.

My only concern is whether the test is indeed reliable and therefore hospitals and conventional doctors eschew it.

A lot of other gene and saliva tests are criticised by doctors and claim they aren’t as reliable as Conventional blood tests. Who know who is right or wrong.

[helvella Administrator Thyroid UK in reply to Wired123]

Given how unreliable some conventional blood tests are, I would question the faith of the doctors in them!

Most recently, we have seen interference with tests from people taking biotin. In the past we have had people with thyroid issues being used to set ranges for thyroid tests! And interference by antibodies. None fully resolved.

[Wired123 in reply to helvella]

Reference ranges are a tricky point, generally it’s based on a sick population as healthy people rarely go to hospital. A true population reference range wouldn’t be any better as you’d still have a lot of sick people in there and you wouldn’t want your levels to be close to the sick people.

Anyway back to my point re DIO2.

Has anyone had these done at a conventional private hospital and had it funded by an insurer. That’s what I would like to know.

Also if anyone knows why conventional Large private hospitals and testing providers are not offering this test as standard.

[SlowDragon Administrator]

Private testing for Dio2

thyroiduk.org/getting-a-dia...