r Biomar ula ke c rs le o & M D f i a o g l Journal of Molecular Biomarkers n a o n Nabhan, et al., J Mol Biomark Diagn 2015, 6:2 r s i u s o J DOI: 10.4172/2155-9929.1000217 ISSN: 2155-9929 & Diagnosis Case Report Open Access Intrafamilial Variability and Clinical Heterogeneity in Two Siblings with NPHP4 loss of Function Mutations Marwa M Nabhan1,2, Susann Brenzinger3, Sahar N Saleem4, Edgar A Otto3, Friedhelm Hildebrandt3,5 and Neveen A Soliman1,2* 1Center of Pediatric Nephrology and Transplantation, Department of Pediatrics, Kasr Al Ainy School of Medicine, Cairo University, Cairo, Egypt 2Egyptian Group for Orphan Renal Diseases (EGORD), Cairo, Egypt 3Department of Pediatrics, University of Michigan, Ann Arbor, Michigan 4Radiology Department, Kasr Al Ainy School of Medicine, Cairo University, Cairo, Egypt 5Howard Hughes Medical Institute, Chevy Chase, USA *Corresponding author: Neveen A Soliman, Center of Pediatric Nephrology & Transplantation, Department of Pediatrics, Kasr Al Aini School of Medicine, Cairo University, Cairo, Egypt, Tel: 0201062132300; Fax: 020223630039; E-mail:
[email protected] Rec date: Nov 27, 2014; Acc date: Jan 26, 2015; Pub date: Jan 28, 2015 Copyright: © 2015 Nabhan MM, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Abstract Joubert syndrome–related disorders (JSRDs) are a group of clinically and genetically pleiotropic conditions that share a midbrain-hindbrain malformation, the pathognomonic molar tooth sign (MTS) visible on brain imaging, with variable involvement of other organs and systems mainly the eyes and the kidneys.