Researchers at the Ohio State University Comprehensive Cancer Center have identified a gene mutation that they estimate dates back to 11,600 B.C. This ancient date of origin makes the mutation the second oldest human disease mutation ever discovered. The investigators believe that the mutation arose in the Middle East about 13,600 years ago, making it second in age only to a mutation in cystic fibrosis that arose between 11,000 and 52,000 years ago.
The researchers found the gene mutation in people of Arabic, Turkish, and Jewish heritage who have a rare inherited vitamin B12 deficiency called Imerslund-Gräsbeck Syndrome (IGS).
The mutation is believed to be a “founder mutation,” meaning that it originated in one individual and was passed down to that individual’s descendants. What makes this mutation so unusual is that such founder mutations are usually limited to a specific ethnic group, but researchers found the newly discovered mutation in people of three vastly different ethnic groups.
Because of the diversity of the populations in which the mutation was present, researchers were not sure at first whether it was a true founder mutation or whether it simply recurred often over time in different ethnic populations. For the study, the investigators examined 20 patients, 24 parents, eight siblings and four grandparents from 16 IGS families. After thoroughly analyzing the gene sequences on either side of the mutation, the researchers were convinced that a single mutational event occurred.
Ohio State University Comprehensive Cancer Center
(Image courtesy of NCCN)
In addition to providing an academically stimulating contribution to life science research and illuminating when the gene mutation first occurred, the investigators’ research will also have real world consequences on the treatment of people with IGS.
“Our findings permit reliable genetic diagnostics in suspected cases of IGS in that this mutation should be considered first when genetically screening patients from these populations,” says principal investigator Stephan M. Tanner, research assistant professor of molecular virology, immunology and medical genetics. According to Tanner, the mutation accounts for more than half of IGS cases in populations studied and about 15 percent of all cases globally.
IGS occurs when a child is born with two mutated copies of either the amnionless (AMN) or cubilin (CUBN) gene. A vitamin B12 deficiency results when a genetic mistake is present in both copies of the two genes and a person can’t absorb vitamin B12 in the small intestine. Children with IGS experience higher risk of infections, fatigue, attention deficit, paralysis, and a fatal form of anemia if left untreated. IGS is treatable with life-long injections of vitamin B12.
The study’s findings were published recently in the Orphanet Journal of Rare Diseases. Funding from the National Cancer Institute helped pay for the Ohio State University Comprehensive Cancer Center research.
Biotechnology Calendar, Inc. is a full-service life science research events and marketing company. We organize catered trade shows at some of the top research university campuses nationwide. If you are a lab supplier or researcher interested in networking at Ohio State University, we invite you to attend our 2012 Ohio State tradeshow. To learn more about our 2012 tradeshow calendar, please click on the button below.
