We present the first case of TSC2/PKD1contiguous gene syndrome in a patient with MMD along with detailed histopathologic, radiologic, and cytogenetic analyses.
This case reveals that although PKD1 and TSC2 are adjacent genes and there is likely cross-talk between the PKD1 and TSC2 signalling pathways regulating mTOR, having independent TSC2 and PKD1 mutations can give rise to a milder kidney phenotype than is typical in PKD1/TSC2-CGS cases.
Clinical awareness and appropriate molecular investigation of TSC2/PKD1contiguous gene syndrome is necessary in all patients with a typical phenotype of TSC in infancy, adolescence, or adult age, because of severity of the renal alterations.
Using fluorescence in situ hybridization and plasmid probe CW23, which spans the adjacent 3' regions of TSC2 and PKD1 genes, we identified a submicroscopic deletion on only one of the chromosomes 16p13.3, thus permitting the diagnosis of the TSC2-PKD1contiguous gene syndrome.