"Exons make up just one percent of the genome, so the exome sequencing process is not only much more economical, but also produces results much faster," says Yaniv Erlich, a graduate student in the Hannon laboratory and co-author of the paper. It only took three weeks for the CSHL scientists to find the mutation as compared with many months required by more traditional methods.

Once the causative mutation was identified, the collaborators combined efforts to screen more than 2,700 anonymous participants in the study. This mass screen revealed the high carrier rate of 1:92 among the cohort. The prevalence of the TMEM216 mutation in the wider population remains to be determined.

Whole-exome sequencing has been gaining momentum over the past few years. "But this is one of the first few studies to use next-generation sequencing to identify a causative mutation underlying a rare genetic disease," says Erlich. The CSHL scientists plan to expand their exome sequencing efforts to screen for mutations that cause other rare as well as common genetic diseases.

"Joubert Syndrome 2 (JBTS2) in Ashkenazi Jews Is Associated with a TMEM216 Mutation" appears in the 8th January issue of the American Journal of Human Genetics. The full citation is: Simon Edvardson, Avraham Shaag, Shamir Zenvirt, Yaniv Erlich, Gregory J. Hannon, Alan L. Shanske, John Moshe Gomori, Joseph Ekstein, Orly Elpeleg. The paper can be found online at cell/AJHG/abstract/S0002-9297(09)00568-0

Cold Spring Harbor Laboratory (CSHL) is a private, not-for-profit research and education institution at the forefront of efforts in molecular biology and genetics to generate knowledge that will yield better diagnostics and treatments for cancer, neurological diseases and other major causes of human suffering.

Source: Cold Spring Harbor Laboratory