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I am trying to find out if I am unmutated or mutated. My results show IgM positive and IgG negative. What's the difference?

It seems that it's vital whether the CLL is unmutated or mutated but I can't seem to find that information anywhere on my FISH test results.

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IGVH mutation status is a special test that is hard to do reliably and I'm not even sure it is done in the FISH testing panels? I'm also unfamiliar with the terminology IgM positive and IgG negative with respect to FISH testing.

It would help if you could reproduce your FISH results here (and change your question to private to this community if you'd prefer that). I know from trying to work out my very basic FISH report that it isn't easy to interpret - I needed expert help.

From what I understand, IgM and IgG are antibodies or immunoglobulins created by B-lymphocytes and their successors - plasma cells and memory cells that remember previous infections. You can be IgM or IgG positive or negative for a particular antigen (i.e. a foreign body that stimulates your immune system). If you are positive, it just means that you've been exposed to a particular antigen (e.g. a virus) and you've developed antibodies to that antigen when fighting off the illness. A negative result just means that you haven't had that illness, or had it such a long time ago that you've lost your immunity or, for those of us with CLL, haven't developed antibodies because our B-lymphocytes don't work, which is why vaccines don't work well for us. To me it sounds like you've had a test for some particular illnesses and that's what your IgM and IgG relate to?

Hopefully someone else more clued up on this than me can better help you.


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It sounds like you have had a quantitative immunoglobulin test... it looks at numbers of antibodies IgA, IgG and IgM in the blood serum... it gives a crude snapshot of how your immune system is operating. They are often done early on to get baseline levels. They may also use the test to get IgG levels, to see if you are deficient, with a consideration to using IVIG to boost the IgG counts and help fight recurring bacterial infection.

You can learn more here


You are very unlikely to get a direct IGHV (note name change) mutation status in a clinical situation. There is a marker however for this mutation, to be found on your flow cytometry. It is CD38. Over 30% you are probably unmutated, under 30% probably mutated, with an accuracy of about 70%. CD38 numbers can also change over time, something to bear in mind, but they rarely flip flop from mutated to unmutated.

There is also Zap70, it is a similar marker, but while the tests have improved, the labs are not very experienced, so results can be wrong...



Thanks Chris for that explanation of IGHV (ex IGVH), CD38 and ZAP70. Last time I had opportunity to ask (and it wasn't a CLL specialist) I was told "Sommatic Hypermutation Incomplete" and the clinician was unsure if that just meant the test itself was complete.

Reading your post above I'm slowly getting a better feel for the difficulties in this area.

Many thanks,



IGHV@ is a family of genes, and while mutation/unmutated divides patients into two large groups, it doesn't tell which gene from the family is driving the CLL bus.

This is a new field called Stereotypy... and looks at specific genes and their effect on a patient's CLL... regrettably these genes aren't tested for clinically at the moment, but this should change in the next 5 years perhaps...

Dr. Hamblin, co-discovered IGHV genes in CLL and his blog is a tremendous source of information...



Thanks for the info, my early FISH test results begin to make a bit more sense: CD38 negative, ZAP 70 negative, Trisomy 12. Does the 'negative' mean below 30% and therefore mutated?


Yup... in general the lower the percentage below 30, the more mutated you are...


Good to know Cllcanada!..... I'm similar to splashsplash in this regard with only "leukocytosis evidence with lymphocytes as the only change since a CBC test Oct. 25, 2010, and "no symptoms of diaphoresis, fatigue, weight loss, hiporexia, or infiltrative syndrome as per adenomegalias, and no hepatosplenomegalia" (Sept. 2017 evaluation/study via citometry of flow-chromasome testing)... A torso-pelvic area catscan they gave me recently on March 11, 2018 (because of a transient case of gastroenteritis) showed all my internal organs thereabouts normal looking/normal size. Thanks!


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