• hearing loss;
  • optic nerve coloboma;
  • paired box gene;
  • PAX2;
  • renal anomalies;
  • renal-coloboma syndrome;
  • vesico-ureteral reflux

Optic nerve coloboma combined with renal disease, also called renal-coloboma syndrome (#120330 in McKusick's Mendelian Inheritance in Man Online, OMIM), a relatively recently characterized syndrome, results from autosomal dominant mutations in the PAX2 gene. Although renal-coloboma syndrome involves both ocular and renal anomalies, some patients are affected with vesico-ureteral reflux (VUR), high frequency hearing loss, central nervous system (CNS) anomalies, and/or genital anomalies, consistent with the expression of PAX2 in these tissues during development. We review here the clinical features of patients with renal-coloboma syndrome and PAX2 mutation. We also review the PAX2 mutations that have been reported to date, and discuss the possible effect of PAX2 mutations on normal development.