AUTOSOMAL-DOMINANT MEDULLARY CYSTIC KIDNEY-DISEASE - EVIDENCE OF GENELOCUS HETEROGENEITY

Autosomal dominant medullary cystic kidney disease (ADMCKD; synonym: m edullary cystic disease, MCD) is an autosomal dominant kidney disorder , sharing morphological and clinical features with recessive juvenile nephronophthisis (NPH), such as reduced urinary concentration ability and multiple renal cysts at the corticomedullary junction. While in NP H endstage renal disease (ESRD) occurs in adolescence, ADMCKD leads to ESRD in adulthood. Recently a gene locus for ADMCKD has been localize d to chromosome lq21 in two large Cypriot families. This prompted us t o examine linkage in three ADMCKD-families, using the same set of poly morphic microsatellite markers spanning the critical region on chromos ome lq21. Haplotype analysis revealed that none of the three families showed linkage to this locus, thus demonstrating evidence for genetic locus heterogeneity. Additional linkage analysis studies need to be pe rformed in order to identify further gene loci cosegregating with this autosomal dominant kidney disorder.