Chromosome 3p23 break with ring formation and translocation of displaced 3p23-->pter segment to 6pter.

An 11 year old boy with short stature, learning difficulties, and no obvious facial anomalies has a ring (3)(p23q29) formed by a break in the short arm at 3p23 and subsequent fusion with 3qter. A second rearrangement involving translocation of the displaced 3p23-->pter segment to chromosome 6 at 6pter is non-reciprocal with no obvious loss of distal 6pter material. The involvement of one chromosome in two separate rearrangements is uncommon. The patient's relatively mild phenotype appears to be associated with the "ring syndrome" and ring instability in division rather than from any segmental aneuploidy resulting from the presence of the two rearrangements.