Three cases of partial trisomy 7q owing to rare structural rearrangements of chromosome 7.

Three cases of partial trisomy 7q are described. One case had duplication of region 7q22.1----q31.2 owing to a de novo direct intra-arm intrachromosomal duplication. The other two cases, first cousins, were trisomic for 7q34----qter, resulting from recombination within the inserted segment of a dir ins(7;17)(q34;q23.1q25.3)mat. All three cases had a number of the already recorded manifestations of partial trisomy 7q, namely strabismus, low set ears, depressed nasal bridge, small nose, hypotonia, and mental retardation.