Polycystic kidney disease is a severe genetic disease occurring in both adult and pediatric patients. The basic characteristic of this disease is the development and progressive enlargement of renal cysts gradually replacing functional kidney tissue. This leads to renal failure in many patients. However, renal cysts may also occur in a number of other diseases, including multisystem syndromes. This complicates differential diagnosis in some patients. In our study, we first focused on the diagnosis and characterization of genotypic-phenotypic relationships in patients with polycystic disease arising in childhood, later we extended our study to adult patients and patients with unclear clinical diagnosis. At the same time, we expanded the portfolio of analyzed disorders to a number of diseases in which the phenotype of polycystic kidneys may occur, and noncystic diseases as well. During our project, massive parallel sequencing was used to analyze 149 patients - 128 with cystic and 21 with noncystic clinically diagnosed nephropathies. At the same time, the findings were verified by Sanger sequencing in 176 relatives of our probands. Mutation detection reached 59% in cystic patients, and 43% in non-cystic patients, respectively. In many patients, molecular genetic analysis revealed a different etiology..
