Tuesday, September 2, 2014
Inherited Disorders and Birth Defects
Balance translocation of 5 and 16
Our daughter is growing quite slowly and recent tests have shown that she has balance translocation between chromosomes 5 and 16. Do you know anything about this? Thanks
Chromosomal translocations can be tricky to understand. A balanced translocation occurs when two pieces of chromosomes break off and switch places with each other. If all the chromosomal material is present, just rearranged – that is, switched places (translocated) - this person should have no health problems since all the chromosomal material needed is present and functioning properly. This is called a balanced translocation. There is no way to tell whether or not a person has one of these rearrangements unless you look at his or her blood to examine the chromosomes.
However, there can be problems if some of the chromosomal material that was switched is lost or duplicated when the chromosomes broke and the switch took place – then there is extra and / or missing information that can lead to birth defects and cognitive problems such as mental retardation. This is an unbalanced translocation.
The specific types of problems or birth defects would depend on the specific areas of the chromosomes that were lost or duplicated in the chromosomes that are translocated and what specific genes are located at these sites. For many unbalanced rearrangements (translocations) it is not possible to predict what abnormalities to expect; for others the medical literature may provide information.
If your daughter’s translocation is balanced, her slow growth may not have anything to do with the translocation. I do not know if you have seen a genetics professional, if not, I would recommend that you so - they would be able to provide you with better information than me. You can locate a genetics center near you at the National Society of Genetic Counselors’ Resource Center website listed below
You might also consider contacting the Chromosome Deletion Outreach support group - they may be helpful. In looking at their website, (listed below) in the Registered Disorders heading, under translocations - I found one cases for a 5 and 16 translocation listed - it was reported to be balanced. These cases come from all over the world. Members of the support group can register and list the chromosome finding of their child. Perhaps they can provide you with additional help.
Anne Matthews, RN, PhD
Associate Professor of Genetics
School of Medicine
Case Western Reserve University