Review: Genetics of Urolithiasis

Urolithiasis constitutes a worldwide health problem with a frequency of up to 15% in the general population. The causes are diverse; exogenous influences and genetic factors act in complex interaction and thereby impede research on stone formation. In recent years, important advances on the elucidation of molecular and genetic bases have been made. Numerous genes for urolithiasis and syndromes associated with stone formation have been identified; however, these account only for a minority of all patients. In spite of a frequency of 75% among urinary calculi, the genetic causes of calcium oxalate stones are unknown except for relatively rare entities such as hyperoxaluria or Dent disease. For patients presenting with uric acid stones, metabolic defects can only be detected in rare instances, but in these cases the molecular bases have been widely resolved. In contrast, the genetic basis of cystinuria has mainly been determined with the identification of two genes encoding subunits of a cystine transporter in the proximal renal tubule. In conclusion, the currently applied biochemical and physical methods of kidney stone diagnosis continue to be the basis of both diagnostics and therapy of stone disease, but they are increasingly supplemented by molecular genetic analysis. Though the basic genetic defects in inborn urolithiasis cannot be cured, their identification considerably contributes to an earlier diagnosis and treatment. Genetic tests will not only make an individual therapy possible, but will also allow a better delineation of entities and thereby well-directed genetic counselling.