Abstract: The duplex collecting system, a malformation of duplex renal pelvis and ureter, is a disease of congenital anomalies of the kidney and urinary tract (CAKUT). The morbidity of this disease is about 0.07%. There is a broad spectrum of forms, or it may accompany with many anomalies of other organs, such as hypospadia, cryptorchidism, vas deferens absence, and hypoplasia of testis and penis. Some of patients may feel no discomfort all through their life, meanwhile others may get irreversible impairment of renal function due to secondary hydronephrosis and calculi. The family history of the duplex collecting system is the most frequent within all CAKUT. Owing to its incomplete penetrance and the undefined pathogenesis, the genetic research of this disease is a challenge. It was found that this disease is related to gene mutations, copy number variants, and interaction between heredity and environment and some other factors. Some pathogenic factors found in human have also been confirmed in animal models, while others could be found either in animal models or human. We herein reviewed the research progress of the pathogenic factors of duplex collecting system.

Key words: Kidney pelvis, Ureter, Genes, Variation（genetics）, Environment