[Multibilly]

Understanding Abnormatlity Terminology

by Multibilly on Fri Mar 29, 2013 12:35 pm

Could somebody help me better understand the shorthand that is used when referring to genetic abnormalities. As an example, in the following article:

http://www.ncbi.nlm.nih.gov/pubmed/21356186

I really want to understand just what sentence below means and what specifically this shorthand "t(4;14)(p16;q32)" means. Is it obvious from the notation, that this is a translocation, and if so, where exactly is the translocation occurring and just what is being translocated,, etc? I realized that I just don't really understand all this and instead just know that I ought to be concerned if I ever see this in one of these notations in my test results

In general, the hypodiploid group with t(4;14)(p16;q32) or t(14;16)(q32;q23) is considered a high-risk group, while the hyperdiploid patients with t(11;14)(q13;q32) are considered a better prognostic group

[john w]

Re: Understanding Abnormatlity Terminology

by john w on Fri Mar 29, 2013 3:57 pm

Terry
I'm in the smoldering study at NIH but not being treated at the present time.Was a cytogenic test performed prior to the CRD treatment.I am curious if the CRD is given regardless of myeloma risk.
Thanks
John

[Dr. Jason Valent]

Re: Understanding Abnormatlity Terminology

by Dr. Jason Valent on Fri Mar 29, 2013 4:54 pm

46 chromosomes contain our DNA (2 copies of Number 1-22 and then the sex chromosomes men XY, woman XX).

The 4 and 14 are referring to the chromosome number. Part of chromosome 4 breaks as does 14 and they come together abnormally and that leads to malignant potential. These are aquired abnormalities in the malignant plasma cell.

The "t" stands for translocation (combining of 2 separate chromosomes) the (4;14) or (14;16) identifies the number of the 2 chromosomes that are combined abnormally and the p or q with number afterward identifies the specific location where the chromosomes come together. The last is indicative of where a potential gene may be turned on or off to set up malignant potential.

[Dr. Jason Valent]

Re: Understanding Abnormatlity Terminology

by Dr. Jason Valent on Fri Mar 29, 2013 4:56 pm

There are specific translocations (ie 4;14) that predict for a poorer prognosis in myeloma. Others are deletion of a chromosome 13 or 17. 14;16 and chromosome 1 abnormalities are also unfavorable.

Extra copies of chromosomes are favorable.

[Multibilly]

Re: Understanding Abnormatlity Terminology

by Multibilly on Fri Mar 29, 2013 9:21 pm

Dr. Jason Valent wrote:
> 46 chromosomes contain our DNA (2 copies of Number 1-22 and then the sex
> chromosomes men XY, woman XX).....

Many thanks Dr. Valent!

[Dianem]

Re: Understanding Abnormatlity Terminology

by Dianem on Sat Mar 30, 2013 3:18 pm

After reading Dr. Valent's response to Multibilly, I'm wondering what does the comment 'extra copies of chromosomes are favorable' mean? On Nov 2011, I was diagnosed with IgMGUS trisomic 7 following a BMA due to a high m spike (1.5) and low WBC (has been around 4 for several years without infections). No CRAB criteria or symptoms. Every 6-8 months my blood levels have been checked and remain stable. I got a second opinion from another hematologist who said 'an extra copy of chromosome 7 is associated with the development amyloid problems and to keep an eye on kidney function.' Are different trisomics (chromosomes 7, 9, etc) more favorable than others? The first hematologist did not mention amyloid issues or recommend anything preventative other than blood tests. Thanks, Diane