balanced translocation

I was told that I have a balanced translocation of my bottom chromosome 1 and 17.  Can you tell me more about this?  What caused this and what does it mean for my future?

[Jordanna Joaquina, MS, CGC]

A chromosome translocation is a chromosome abnormality caused by the rearrangement of genetic material between different numbered (also called non-homologous) chromosomes.

Chromosome translocations can be characterized as balanced or unbalanced.

A balanced translocation involves an apparently even exchange of genetic material resulting in no loss or gain of total genetic information. A balanced translocation does not typically result in physical and/or mental abnormalities.

An unbalanced translocation involves an uneven exchange of genetic material resulting in a gain or loss of total genetic information. An unbalanced translocation is more likely to result in physical and/or mental abnormalities.

Although people with balanced chromosome translocations do not usually have mental and/or physical abnormalities, they may be at increased risk to have pregnancy losses, stillbirths, and children with chromosome abnormalities. For example, people who carry a balanced Robertsonian translocation involving chromosome 21 have a higher chance to have a child with Down syndrome.

The risks, however, are dependent upon the specific chromosomes involved and their breakpoints. We recommend that you meet with a genetic counselor, who can review your results, as well as your personal and family history for a more accurate risk assessment. You can find a genetic counselor at the National Society of Genetic Counselors website or through companies like mine, AccessDNA. You can find more information about chromsome translocations also at AccessDNA.

[pumpernickelbred]

A related discussion, When to test for chromosom translocation was started.