Massive diaphragmatic hernia and renal abnormalities in two unrelated families

Abstract

Two unrelated patients recently gave birth to male babies which were either stillborn or died soon after birth with massive diaphragmatic hernias. On autopsy, 2 babies from one woman (H.B.) showed polycystic kidneys, while the baby examined from the second woman (T.J.) showed unilateral renal agenesis. In addition, each of T.J.’s babies had a meningomyelocoele. Karyotypes from H.B., her husband, and her 2 stillborn children, showed no abnormality by Giemsa banding. Her family history was consistent with an X-linked recessive gene, but no such gene has been previously described. Similar abnormalities have only been described in triploids, trisomy 18 and possible partial trisomy 16. Karyotypes were not performed on the babies of T.J., but T.J. herself shows a small extra band on the distal region of one X chromosome. The aetiology of this band is uncertain, but it appears to be translocated from the distal region of the q arm of one chromosome 13 (band 13q33). Her normal daughters have been screened for this minute translocation and 2 of the 3 appear to carry it. Unilateral renal agenesis is a known X-linked gene. Whether the diaphragmatic hernia seen in both families might also be X-linked or whether it and gene(s) causing meningomyelocoele might be translocated from chromosome 13 (or elsewhere) will be discussed.