LADA, Type 1, genetic differences ?

[HelenM]

Following up the thread on inheriting diabetes. I found this article which explains the genetics of diabetes. I don't find the subject easy (which is why I was looking it up) andIt doesn't specifically mention LADA or 1.5 but it does include this.

Diabetics who have inherited DR3 (but not DR4) develop diabetes at an older age, and tend to have antibodies against pancreatic beta cells but not against insulin. These people are also more likely to develop thyroid autoimmune disease.
Diabetics who have inherited DR4 (but not DR3) tend to develop diabetes earlier in life and have an immune reaction against insulin.
Diabetics who inherit both DR3 and DR4 develop diabetes at the youngest age and have the highest levels of antibodies against insulin.
my underlining
from Genes Can Cause Type 1 Diabetes (http://www.genetichealth.com/DBTS_Genetics_of_Type_1_Diabetes.shtml)

I might be completely misunderstanding it but if people with LADA only have the DR3 allele it might suggest a difference (apart from age at onset) between them and type 1. as they would not have 'immune reaction against insulin'. (make it slightly easier to control?)


From a personal point of view I found it interesting as my mother has thyroid disease (also diagnosed late in life) and a cousin has also developed LADA.

[NoraWI]

I have read the study that you quote and it seems sound to me. I, too, have a slow-progressing LADA as well as additional autoimmune conditions such as Hashimoto's thyroiditis, vitiligo, rosacea, RP, etc. I was diagnosed at age 62. So was my maternal grandmother. Not my mother but she had all sorts of diabetic symptoms and even an amputation towards the end of her life. She lived to be 91, so who knows. I think the medical profession ceases to worry about or test for diabetes in people of advanced age. And, yes, the slow-progression of LADA means that there is still some endogenous insulin production going on and that makes it somewhat easier to control. In my case, I find that a lowish-carb diet and extreme care in dosing insulin (keeping the numbers as small as possible in MDI) help immensely.

[Kate H]

From a personal point of view I found it interesting as my mother has thyroid disease (also diagnosed late in life) and a cousin has also developed LADA.


many women develop hypothyroidism after menopause

[Harold]

Not sure i would take any article seriously that sounds like there are antibodies for insulin. Insulin is a hormone not a cellular body and antibodies act on cellular bodies.

[E-NICE]

Genes Linked to Autoimmune Diseases - To Your Health - MSNBC.com (http://www.msnbc.msn.com/id/16738416/site/newsweek/from/RS.3/)

[jen_slc]

Not sure i would take any article seriously that sounds like there are antibodies for insulin. Insulin is a hormone not a cellular body and antibodies act on cellular bodies.Antibodies against insulin can and do exist though because antibodies don't act on cellular bodies, they act on antigens, which are usually proteins or carbohydrates. When we say we have antibodies against a certain bacteria, it means we have antibodies against a particular protein or carbohydrate that is found on the outside of that bacteria, not against the entire cell. :)

Interesting article, thanks for posting!

[BriOnH]

Antibodies against insulin can and do exist though because antibodies don't act on cellular bodies, they act on antigens, which are usually proteins or carbohydrates. When we say we have antibodies against a certain bacteria, it means we have antibodies against a particular protein or carbohydrate that is found on the outside of that bacteria, not against the entire cell. :)

Interesting article, thanks for posting!

Wouldn't the antibodies attack Humalin R insulin then? From what I remember from medical immunolgy - the antibodies only attack a certain sub sequence in a protien (not iterating through each aa) - I would imagine this would be the action site<?> of the enzyme in this case.

[jen_slc]

Wouldn't the antibodies attack Humalin R insulin then? From what I remember from medical immunolgy - the antibodies only attack a certain sub sequence in a protien (not iterating through each aa) - I would imagine this would be the action site<?> of the enzyme in this case.Yeah, that's true. When I said they act on proteins or carbohydrates, I meant that they bind to a particular sequence, not the entire thing - I was just trying to avoid a complex description. :D

[HelenM]

Wouldn't the antibodies attack Humalin R insulin then
I think this is where my original thought processes were going.

Some people have a gene that causes antibodies against the pancreatic cells, some in addition may have antibodies to insulin. These latter are most likely to develop diabetes early in life (classic juvenile type 1)These not only have to replace the insulin but their body reacts in some way against the insulin. Others,(who tend to develop diabetes later) replace the naturally produced insulin with injected insulin which then works as it should.

Reading on this site I seem to get the impression that my own diabetes and that of many others with LADA is not subject to the erratic swings of BS that many type 1s seem to experience. Its normally explained by reference to residual insulin production which might or might not disappear. If this genetic data is correct then there are real differences, more than one type of autoimmune diabetes. I haven't found anything to suggest this elsewhere