Some American physicians are using so-called embryonic stem cells to treat patients without proper scientific trials. A feature in the Sacramento Bee alleges that two Californian health professionals are attracting desperate patients by word of mouth and the internet and referring them to clinics overseas in countries like the Ukraine, Mexico and the Dominican Republic. “They have no scientific credibility. They don’t even aspire to scientific credibility,” says Dr Evan Snyder, a leading stem cell researcher from the Burnham Institute in La Jolla.

The Bee highlighted the dubious professional background of two of these practitioners. Dr William C. Rader, of Medra Inc, uses stem cells from aborted foetuses. He is a psychiatrist who has run eating-disorder clinics. Another is an osteopath at Mission Viejo, David Steenblock, who has been in trouble with California’s Osteopathic Medical Board after mishaps at his practice in 1994, one of them fatal. They treat conditions like cerebral palsy, multiple sclerosis and Lou Gehrig’s disease. Although some of their patients are enthusiastic, most of them have not experienced major changes in their health, despite spending tens of thousands of dollars.