An unbalanced submicroscopic translocation t(8;16)(q24.3;p13.3)pat associated with tuberous sclerosis complex, adult polycystic kidney disease, and hypomelanosis of Ito
- Bert H J Eussena,
- Gabriella Bartalinib,
- Lida Bakkera,
- Paolo Balestrib,
- Carmela Di Luccab,
- Jan O Van Hemela,
- Hans Dauwersec,
- Ans M W van den Ouwelanda,
- Carrie Ris-Stalpersd,
- Senno Verhoefa,
- Dicky J J Halleya,
- Alberto Foisb
- aDepartment of Clinical Genetics, Academic Hospital Rotterdam, PO Box 1738, 3000 DR Rotterdam, The Netherlands, bUniversità degli Studi di Siena, Istituto di Clinica Pediatrica, Siena, Italy, cDepartment of Human Genetics, Leiden University, Leiden, The Netherlands, dLaboratory of Paediatric Endocrinology, Academic Medical Centre, University of Amsterdam, Emma Children's Hospital AMC, Amsterdam, The Netherlands
- Dr Eussen
- Revised 31 October 1999
- Accepted 3 November 1999
Abstract
We report on a familial submicroscopic translocation involving chromosomes 8 and 16. The proband of the family had a clinical picture suggestive of a large deletion in the chromosome 16p13.3 area, as he was affected with tuberous sclerosis complex (TSC) and had α thalassaemia trait, and his half brother, who also had TSC, may have suffered additionally from polycystic kidney disease (PKD). FISH studies provided evidence for a familial translocation t(8;16)(q24.3;p13.3) with an unbalanced form in the proband and a balanced form in the father and in a paternal aunt.
The unbalanced translocation caused the index patient to be deleted for the chromosome 16p13.3-pter region, with the most proximal breakpoint described to date for terminal 16p deletions. In addition, FISH analysis showed a duplication for the distal 8q region. Since the index patient also had hypomelanosis of Ito (HI), either of the chromosomal areas involved in the translocation may be a candidate region for an HI determining gene. Furthermore, it is noteworthy that both carriers of the balanced translocation showed a nodular goitre, while the proband has hypothyroidism.








