DIO1 / DIO2 Mutation

[Blosstan]

Hi these are my gene test results:

DIO1

(rs2235544) AA mutation

(rs11206244) CC normal

DIO2

(rs2250145)AG

A is normal and G is mutation

am I right in thinking these mutations impair T4 to T3 conversion?

Many thanks

[jimh111]

These are just minor variations between people, not really mutations in the way we would usually use the word. The CC genotype of the rs225014 polymorphism in the deiodinase 2 gene (DIO2) leads to minor cognitive problems in patients on levothyroxine monotherapy. My view is that little is known about the detailed effects of these natural variations between people and their effects seem to be minor although some are associated with higher risk for other conditions.

It's not a question of whether they impair T4 to T3 conversion but which type of conversion and to what extent. Logically if someone took sufficient L-T3 to restore their normal level of fT3 then they would be as healthy as they always were. Many patients need more than this so clearly their problems are not caused by minor genetic variations.

[DippyDame]

As an example...

I have the variant Dio2/homozygous - discovering this, and taking on board the possibility of poor conversion, I decided to add T3 to my prescribed T4 dose (to which I was not responding) and started to titrate T4/T3 combinations.

After 5 months of many trial titrations I found only a small improvement....it looked as if poor conversion was not the answer

It turned out that my problem is not (wholly) the polymorphism but rather that I have a form of Thyroid Hormone Resistance. My body needs a lot of T3-only....long rrather complicated story but not for now.

Having said that the Dio2 test pointed me in the direction of further investigation, so for me it was helpful. As was the amazing advice I received from experienced members here.

Are you hoping that the Dio2 test will prove poor conversion and help you to get a T3 prescription?

Poor conversion can also be evidenced by your labs......look for high FT4 with low FT3 .

This can often be improved by ensuring that folate, ferritin, vitamin D and vitamin B12 are all optimal.

Some medics now prescribe a trial of T3 on the basis of a Dio2 polymorphism....perhaps in some cases, too brief a trial!

The endo I saw conceded that the addition of T3 might help but wouldn't prescribe it...we parted company and I then received the excellent guidance that I needed on this forum.

I'm glad I had the thyroid genetic test, learning about it was an important step in my thyroid journey.

I see jimh111 has responded, he has played a part in my own recovery...listen to him