The Oculo-cerebro-renal syndrome of Lowe is an X-linked recessive disorder characterised by mental and growth retardation, renal rickets with renal tubular acidosis, generalised aminoaciduria, hypotonia, cataracts, glaucoma and frontal bossing. Manifestations of this syndrome were seen in a girl with no family history of the disorder, but who was found to have a de novo balanced X/3 translocation, with a breakpoint at Xq25. She had also inherited a balanced 14/17 translocation from her father. It is postulated that the clinical picture may be the result of disruption of the X chromosome within the gene at the locus for Lowe syndrome, with non-random inactivation of the normal X, which may permit the expression of this X-linked recessive disorder in a girl.