Complete trisomy 5p owing to de novo translocation t(5;22)(q11;p11) with isochromosome 5p associated with a familial pericentric inversion of chromosome 2, inv 2(p21q11).

A boy with a de novo translocation (5;22) and isochromosome 5p associated with a pericentric inversion of chromosome 2 (p21q11) is described. The pericentric inversion was also present in the mother. The main clinical features of the 'complete trisomy 5p' syndrome were present in the proband.