Omicron, a rare genetic disorder that, among other things, causes blindness and deformities of the face, received a boost Thursday when an independent clinical research committee concluded that a group of children’s cases appear to be unrelated to a cluster of unexplained cases that have been linked to Omicron.
“These preliminary findings, the first of their kind in the community, are consistent with the current trajectory and linearness” of recent reports, the committee wrote in a report published Thursday in the New England Journal of Medicine.
This is a striking shift from an assessment that was issued in late 2015, when the Omicron clinical research committee — made up of representatives from several organizations — said two members of its committee who have diagnosed Omicron patients think the strange cluster may be linked to the rare genetic disorder.
It added: “Only 20 cases in the United States have been reported to date, and the rate of diagnoses might be reasonably expected to be higher, suggesting additional mutations have arisen and these cases are the result of those mutations.”
Since then, Omicron cases have popped up in a second group of patients in Missouri. In a 2014 rare-disease study, one case is reported out of a sample of 1,176 cases of blinding age-related macular degeneration cases. That told an atypical story, the study said, and the research committee referred the condition to Omicron. It sent letters to people diagnosed with the condition, asking them to call a hotline or an ophthalmologist who was familiar with the condition to help determine the cause of the anomalies. The phones remained unanswered, and the team said it got little information in return.
This leaves open the possibility that in both groups of cases, a genetic defect has disrupted a normal process for creating healthy cells. But so far, the patients do not share any genetic mutation.
The incidence of Omicron is low, according to epidemiologists. Prior to 2014, there were only 14 cases of the condition reported nationwide. The FDA now estimates there are about 220 cases across the country, making the threshold for an “autopsy” of the syndrome 20 cases out of 1 million of the population. The FDA wants more information from researchers to confirm what the Ohio center and its colleagues have done, but the research committee report said in its interim report that its results “are consistent with the rising rate of identified mutations” in Omicron cases.