Predicting the clinical presentation of chromosomal mosaic individuals is very difficult.  In this section, we have tried to summarize what is known about the effects of mosaicism for each chromosome.  Looking at published case reports, there is often a broad range of clinical outcomes reported, even when the same chromosome is involved.  It is important to recognize that the cases that are published may not accurately reflect the frequency of possible outcomes.  There is generally a tendency to publish cases with the worst outcomes or unusual presentations, thus neglecting the less severe, more ordinary and often more frequent outcomes.   Since there is little systematic data about clinical outcome, this section can only be considered a guide to patients and families.  This section is reliant on our own judgment and interpretations of the data rather than proven facts.

 It is not our intention to encourage patients and families to try to predict their own outcome.  We encourage you to browse the whole web site to gain an understanding of how chromosomal mosaicism occurs and why there is so much variability in expression of these conditions.  We hope that you use this section to get an idea of the kind of health conditions certain individuals diagnosed with chromosomal mosaicism have experienced.