Abstract

The association of nephropathy, Wilms' tumour and genital abnormalities is known as Drash syndrome. Two of these features are also seen in the WAGR (Wilms' tumour, aniridia, genito-urinary abnormalities, mental retardation) complex, known to be associated with deletions of chromosome region 11p13. We have carried out karyotypic and molecular studies in 10 Drash patients, 5 males and 5 females. All the males had a 46XY karyotype as did 3/5 of the phenotypic females, the other two having a 46XX karyotype. One of the 46XX females also had a deletion of region 11p13-p12, the only detectable autosomal chromosome abnormality in any of the patients studied. Lymphoblastoid cell lines were prepared from 6 of the Drash patients and were used in dosage studies using a variety of DNA probes from the 11p13 region. There was no evidence of microdeletions in any patient with a normal karyotype. Because of the 46XY karyotype in phenotypic females, selected X and Y chromosome loci were analysed and all found to be normal. Although Drash syndrome is likely to be of genetic origin, there are no readily detected deletions within the 11p13 region.