Mutations of the PKD2 gene in Korean patients with autosomal dominant polycystic kidney disease

Autosomal dominant polycystic kidney disease (ADPKD) is one of the common Mendelian disorders in humans and the most frequent genetic cause of renal failure in adults. It is characterized by progressive formation and enlargement of cysts, typically leading to end-stage renal disease. The disease is genetically heterogeneous and can be caused by a mutation of one of two genes, polycystic kidney disease 1 (PKD1) and polycystic kidney disease 2 (PKD2) gene. Until now, ∼ 78 mutations of the PKD2 gene have been reported in European and American populations, but little information is available on the pattern of mutations present in the Asian population. To clarify the molecular genetic characteristics of the PKD2 gene causing ADPKD in the Korean population, the 15 coding exons of PKD2 gene were amplified and analyzed by SSCP analysis in 163 Korean patients with ADPKD. Five mutations were identified: one nonsense mutation, R742X in exon 11; one small deletion, 1436 del 4bp in exon 6; three missense mutations, T419A in exon 5, Y527C in exon 7, I680T in exon 10. All the mutations except for R742X are reported here for the first time. The detection of additional disease-causing PKD2 mutations will help in identifying the location of the important functional regions of polycystin-2 and help us to better understand the pathophysiology of ADPKD.