For the first time in the world: in a family from Israel, 25 new genes that cause deafness were discovered in Israel and Israel

One of the genes, called ATOH1, was found for the first time in the world to be involved in deafness. Family members in Israel are the first people in the world to be found to have a mutation in this gene - which is responsible for hearing loss

Among the Jewish population in Israel, science has so far known about seven genes involved in hearing loss. Now, thanks to a new study led by Dr. Tzipi Braunstein and Prof. Keren Avraham from the Sackler Faculty of Medicine at Tel Aviv University and in collaboration with researchers and doctors from medical centers throughout Israel, the US and the Palestinian Authority, the number of genes involved in hearing impairment has jumped to 32 - with consequences Immediate treatments for genetic counseling, treatment and rehabilitation of the hearing impaired. Furthermore, the researchers from Tel Aviv University identified in one Israeli family a first mutation in a gene that until now was not known in the world to be involved in hearing impairment. The groundbreaking research was recently published in the journal Clinical Genetics.

More than 150 genes are known to science to be involved in hearing loss, but the mutations in these genes are very different in their distribution between populations in the world, and also between Jews of different ethnicities. Among the Jewish population in Israel, seven genes out of the 150 known were recognized as being responsible for the various deficiencies. Now, in a study that included 88 families of Jews in Israel suffering from hearing impairments, the team of researchers from Tel Aviv University was able to identify 25 additional genes. The discovery is of crucial importance regarding the treatment of the hearing impaired in Israel.

24 of the 25 genes added in the Jewish population are world-known deafness genes, but most of the mutations found by the researchers are new and unique to the Jewish population in general and some, to certain ethnic groups in particular. The other gene, called ATOH1, was found for the first time in the world to be involved in deafness. Members of one family in Israel are the first people in the world to be found to have a mutation in this gene - which is responsible for hearing loss.

"It is known that this is an important gene in the ear," explains Prof. Avraham, "because without it, hair cells cannot form - the same cells thanks to which we hear. In fact, the gene is also responsible for the production of brain cells - so that in its absence the child will die in the womb even before birth. Until today, science knew about a mutation at the end of this gene, which causes hearing impairment, but only among mice. We found a similar mutation among members of one large family in Israel - the first humans in the world with a mutation in ATOH1. I believe that thanks to this research, more families will be discovered, in Israel and in the world, with mutations in this gene, and new treatment options will be developed for those suffering from hearing loss as a result of the congenital mutation - which include gene therapy."

Prof. Avraham adds: "We conducted a large survey among the Jewish population in Israel who suffer from varying degrees of hearing impairment. For this purpose, we used advanced technology of deep genetic sequencing and built a genetic test called HEar-Seq, which allows scanning for mutations in all 150 genes known to be involved in one way or another in hearing loss, and in several dozen additional genes that have a role in the hearing system and therefore have the potential to be involved in deafness. Such a test makes it possible to understand the distribution of genes and mutations that cause hearing impairments in the Jewish population in Israel as a whole, and in the different denominations in particular.

Using the test, we looked for mutations in the relevant genes in 88 families of Israeli Jews with various problems of hearing loss, from congenital deafness to hearing loss in old age, and we identified mutations in 25 additional genes, which were previously unknown among the Jewish population. This is an important discovery with immediate therapeutic implications, which include genetic counseling, prevention of additional cases in the family with the help of prenatal diagnosis or in vitro fertilization, and in many cases also treatment and rehabilitation adapted to the specific gene in the family. The findings of the study allow doctors in Israel to provide personalized treatment to patients suffering from hearing loss as a result of genetic mutations."

More of the topic in Hayadan:

• Researchers at Tel Aviv and Bethlehem universities have uncovered genes for deafness in both nations
• Another factor that may lead to hearing loss - the absence of micro-RNA molecules
• A mutation unique to Ashkenazim causes congenital deafness and gradual blindness