How the inherited gene causes the miscopying is unknown.

The new cancer gene reported last week considerably broadened that mystery because it showed that a very similar miscopying occurs in the tumor cells of individuals who inherit the gene.

Genetic instructions get garbled through inheritance, or in the miscopying of DNA when a cell divides or from physical damage wreaked by carcinogens like tobacco smoke, ultraviolet light and radiation.

Its author is unknown; the manuscript is signed by a monk named Hyngham, but he was probably only the scribe since some of the textual oddities are believed to derive from his miscopying of parts of the text because he was not familiar with it.