TCF2 gene mutation leads to nephro-urological defects of unequal severity: an open question.

There are several genes known to be involved in simple renal or combined renal-extrarenal aberrations. Of these, the transcription factor 2 gene is expressed longer, from very early embryogenesis and throughout organ development during pregnancy. Transcription factor 2 gene encodes the hepatocyte nuclear factor-1 beta transcript, which is a member of the homeodomain-containing superfamily of transcription factors. Transcription factor 2 gene mutations may be associated with a wide variability in severity and pattern of clinical symptoms. Transcription factor 2 gene mutation may be responsible for approximately one-third of children having isolated renal cysts, multicystic dysplastic kidneys, oligomeganephronia, hypo-dysplastic kidneys, horseshoe kidneys, and hyperechogenic kidneys. The wide clinical presentation of hepatocyte nuclear factor-1 beta mutations suggests a broad role of this transcription factor throughout development. The complexity of phenotypes is quite interesting because it could depend on the vast expression time of this gene derangement during fetal development or on different gene-gene and gene-environmental interactions during different stages of embryogenesis. The current literature is reviewed concerning the malformations that have been associated with transcription factor 2 gene mutations involving primarily the kidneys and occurring both in an isolated form and in association with other defective organs to characterize the patterns of this genetic disease.