Prenatal Diagnosis of Joubert Syndrome With Whole Exome Sequencing

Joubert syndrome(JS), was first discovered by Marie Joubert, which is a rare autosomal recessive inherited disease belonging to ciliopathy with the causative mutation of genes. A 27-years-old woman was referred to our clinic for advanced research over the detection of fetal renal cyst.We observed policycstic kidney in detailed examination.INPP5E mutation was detected on chorion villus sampling.We were thought may be this findings will be associated with the syndrome, primarily joubert syndorme (JS),upon detection the vermis hypoplasia, policyctic kidney and molar teeth sign was observed on USG in the 23rd week of pregnancy.The vermis hypoplasia, posterior fossa expansion and bilateral polycystic kidney was seen on MRI and radiologist was reported as Dandy-Walker depend on this findings.They did not pay attention to the molar tooth finding.We were explanied prognosis and suggeted termination to the family.The family was accepted and fetus was terminated. The most common characteristic brain image of JS is the molar tooth sign(MTS) on the axial plane, cerebellar vermis (CV) hypoplasia, and a deepened interpeduncular fossa.The MTS is the key diagnostic feature for this disease. So far, more than 30 causative genes have been found for the various subtypes of JSRD.One of them is INPP5E. Defects of additional extra-nervous systems involve polycystic kidney disease, retinal degeneration, skeletal defects (such as polydactyly), and liver disorder. Joubert Syndrome can be diagnosed in prenatally period.MTS can be seen easily with usg during prenatal period.The vermian hypoplasia and additional organ anomalies must be brought to mind JS and MTS should be searched.