One day in March 2005, Reed Cartwright jotted his thoughts on his blog, De Rerum Natura, after reading a paper that had just been published in Nature. Cartwright, then a PhD student in genetics at the University of Georgia, was skeptical.
Susan Lolle and colleagues at Purdue University had found a peculiar phenomenon regarding a mutant gene, called hothead (hth), in Arabidopsis. In parents carrying the mutant hth gene, 10% of the progeny ended up not carrying it, and instead carried a reverted grandparental allele not found in their parents. They postulated that the pattern was due to a non-Mendelian inherited cache of RNA that served as a backup for restoring ancestral alleles (S. J. Colle et al., Nature, 434: 505-9, 2005).
Cartwright didn't agree, and he blogged about an alternative hypothesis. He argued that the hothead gene mutation may cause an increase in mutagenic...