Malcolm Ritter writes about a bizarre experiment in which mice inherited a genetic trait for white-tipped tails without inheriting the actual gene that causes white-tipped tails. Weird! This flies in the face of Mendelian genetics, but apparently it's not the first times scientists have noticed such a phenomenon. According to one scientist who analyzed the data, which was published in Nature
That phenomenon, called paramutation, was shown 50 years ago in corn and later in other plants. Similar findings have also been made in animals, but the new work is notable because it presents evidence for how it happens…
The scientists believe that RNA, instead of DNA, transmitted the trait.
RNA normally delivers instructions from genes to a cell's protein-making machinery, so it makes sense that it might be involved in transmitting a gene's effect. Just how it's operating in the mice is not clear, said lead study author Minoo Rassoulzadegan of the University of Nice Sophia Antipolis in Nice, France.
Image courtesy Nature