Sanford-Burnham researchers don’t often get the opportunity to meet patients who benefit from their research. But last month, a four-and-a-half year old girl named Alma came to La Jolla to visit Dr. Hudson Freeze’s laboratory. Alma and her family live in Iran, but were in the United States for six months while she received treatments at the Mayo Clinic. Alma has an inherited genetic disorder that causes her to suffer from developmental problems and a severe skin ailment. For most of her life, the cause of Alma’s health issues was unknown. But that has now changed, thanks to a new study led by Dr. Joseph Gleeson at the University of California, San Diego (UCSD). In the study, which appeared July 15 in the journal Cell, Dr. Gleeson, Dr. Freeze and their colleagues helped identify the gene mutation responsible for Alma’s condition. In doing so, they also uncovered a new inherited disease that will be classified within a family of similar conditions known as Congenital Disorders of Glycosylation (CDG).
CDG is a group of many diseases, each characterized by a mutation in a different gene required for proper glycosylation, the process by which cells add sugar molecules to proteins in order to help them function properly. Glycosylation is so important that people who inherit a mutated gene encoding just one glycosylation enzyme, like Alma, are born with CDG.
These inherited diseases are extremely rare, though more are being identified as researchers pinpoint glycosylation gene defects and as doctors become more aware of the symptoms. In the past decade, mutations in 25 different genes have been identified as causes of CDG. And now this Cell study adds another to the list.
“This gene, called SRD5A3, was thought to be involved in a different process, but we found that it really codes for an elusive glycosylation enzyme that evaded detection for over 30 years,” Dr. Freeze explained. “Based on the clinical symptoms of other patients lacking this gene, Bobby Ng, a technician in my lab, thought that one of the patients in our own collection of patient samples also had a defect in this gene. He was right – and that’s how we came to meet Alma.”
While Alma and her parents were visiting Dr. Freeze last month, Dr. Fred Levine, director of Sanford-Burnham’s Sanford Children’s Health Research Center, heard about the little girl and her medical problems. Drawing on his experience as a pediatrician, Dr. Levine proposed giving Alma fresh frozen plasma to alleviate her debilitating skin issues. The family hopes to return to California soon to receive this treatment at Rady Children’s Hospital San Diego.
Since Alma’s visit, Dr. Freeze has also found a commercial product made from pine needle extract, which contains the chemical compounds that Alma’s cells can’t produce because they lack SRD5A3. He hopes that applying this material to the skin might bring the little girl some relief, at least for her skin condition.
“We are now analyzing this material to determine how much of these chemicals it actually contains and we may be able to test this material when the family returns to San Diego,” said Dr. Freeze. “So stay tuned.”