Evaluation Recommendations

From our review of clinical records from patients in the Joubert Syndrome Foundation, we have found many with co-existing medical conditions at a frequency sufficient to warrant a set of guidelines for the evaluation and monitoring of all patients with Joubert Syndrome and Related Disorders. These evaluations are necessary for two reasons. First is for proper diagnosis of the child, as we find that approximately 20% of patients display features indicating a subtype of Joubert syndrome or a related syndrome. Second is to try to prevent medical complications from these associated conditions, which through proper screening might be avoided. However, because our total knowledge of Joubert syndrome and its complications are limited, our recommendations will need to be evaluated and changed as new information becomes available. Download the JSRDF Recommendations for Evaluation PDF for more information.

Dr. Joseph G. Gleeson, Dr. Melissa A. Parisi, Dr. Bernard L. Maria, Dr. William B. Dobyns – Medical Advisors of the Joubert Syndrome Foundation

Inheritance Patterns

We all carry the same genes, including all of the genes known for JSRD, and variations within our genes are what make us unique. Someone who has been diagnosed with JSRD has a change in their gene(s), typically referred to as a mutation that prevents it from making its protein or doing its “job” within our body.

Joubert syndrome is typically inherited in an autosomal recessive manner. Individuals with a recessive form of JSRD have mutations in both copies of a gene associated with JSRD, thus they no longer have a working copy of this gene within their body. Parents of an individual diagnosed with an autosomal recessive form of JSRD are both unaffected carriers. Carriers are individuals that “carry” one nonworking copy of the JSRD gene on one chromosome and one working copy on the other. When both parents are carriers for an alteration in the same JSRD gene, there is a 1 in 4 or 25% chance that the child will be an unaffected, non-carrier, a 1 in 2 or 50% chance that the child would be an unaffected carrier (like the parents) and a 1 in 4 or 25% chance that the child would be affected with JSRD, with each pregnancy. It is important to note that there could be intrafamilial variability, which means that if two or more individuals in the same family are affected with JSRD, each may be affected in different ways. Download the JSRDF Inheritance Patterns PDF for more information.

Download: JSRDF Inheritance Patterns