Is RNA inheritance possible?

Evidence for non-DNA-based inheritance has been found in a particularly unstable plant gene, researchers suggest in Nature this week. Robert Pruitt and colleagues at Purdue University in West Lafayette, Ind., found that Arabidopsis plants homozygous for recessive mutant alleles of particular gene may inherit genomic information that is not found in the parent plant, but that existed in earlier generations.

"We can imagine two parallel pathways, one of DNA-based inheritance, and in the background you have this other which might be RNA—or an odd form of DNA-based inheritance we don't understand," Pruitt told The Scientist.

Pruitt's team was investigating HOTHEAD, a gene responsible for wax cuticle production that, when mutated, causes organ fusion. Previous research has shown unusual point mutation instability in the gene in Arabidopsis, which results in a high frequency of wildtype plants from mutant parents.

In the latest study, Pruitt's team used polymerase chain reaction to determine ...