NEW YORK— Scientists at Fordham University have reported the discovery of the genetic mutation responsible for Nemaline Myopathy (NM), a rare neuromuscular disorder that affects individuals of Ashkenazi Jewish descent and can cause breathing difficulties, low muscle tone and delayed motor skills. Ashkenazi Jewish children with NM often die before the age of 20.

Berish Rubin, Ph.D., chair of the department of biological sciences, and Sylvia Anderson, Ph.D., reported in an article published in Human Genetics, that they had identified the deleted segment of a gene that encodes the protein nebulin, which is critical for muscle function. They made the discovery using DNA samples gathered from as far away as Australia.

“The identification of the causative mutation will now allow for the genetic screening for this disease,” said Anderson.

Genetic testing conducted in the Fordham laboratory reveals that approximately 1 percent of people of Ashkenazi Jewish descent carry this mutation, said Rubin. Couples in which both of the parents are carrying the NM mutation have a 1 in 4 chance of having a child with NM. Carrier testing for people of Ashkenazi Jewish descent is now available, upon request, through Dor Yeshorim: The Committee for Prevention of Jewish Genetic Diseases, and general screening should soon be available as part of the Jewish genetic screening panel at other commercial genetic testing laboratories. The ability to screen for NM carrier status is expected to reduce the incidence of NM.

This discovery represents the second disease-causing genetic mutation iden-tified by the Fordham research team. In 2001, Rubin and Anderson reported the identification of the genetic cause of Familial Dysautonomia (FD), a neurological disorder of the sensory and autonomic systems. Their discovery has resulted in widespread FD carrier testing.

“Many research laboratories have attempted, with little success, to identify the cause of a single genetic disease,” said Rabbi Joseph Ekstein, executive director of Dor Yeshorim. “It is amazing that this group has identified the mutations responsible for two genetic diseases and has also developed therapeutic modalities that have reduced the impact of the FD-causing mutation, thereby significantly reducing the severity of the disease.”

Parents who have children with NM are very pleased, said a mother of two children with NM of the breakthrough. “This discovery will allow carrier testing to be performed on our healthy children who then will be able to enter marriage with the confidence that they will not have children who suffer from NM.”

This research effort was funded by grants from Dor Yeshorim and the DYHM Foundation. Families requiring further information should feel free to contact either Rabbi Ekstein at 718-384-2332 or Dr. Rubin at 718-817-3642