It's a number that he says has been spotted in many places, but In the Pipeline's Derek Lowe wonders whether researchers really know the causes of 4,500 diseases. The figure, Lowe adds, is usually used in reference to the National Institutes of Health's translational medicine program.
For example, a new Clinical Pharmacology & Therapeutics article references it, saying that "we now know the causes of more than 4,500 diseases, but it has been estimated that more than 90% of these still have no effective treatment."
Lowe writes that this figure seems rather high, and he tries to trace it back to its source, which appears to be the Online Mendelian Inheritance in Man Gene Map. The scoreboard there says that the molecular bases of 4,838 phenotypes are known.
"But read the fine print: 'Phenotypes include single-gene mendelian disorders, traits, some susceptibilities to complex disease … and some somatic cell genetic disease …'" he writes. "My guess is that a lot of what's under that banner does not rise to 'knowing the cause,' but I'd welcome being corrected on that point."