Daily Archives: 27/01/2013

It’s been pointed out that the concept of “Junk DNA” came not just from the observation of apparently non-coding genetic elements and their interpretation as “parasitic”, but from a theoretical prediction by the noted evolutionary biologist Susumu Ohno in 1972. Ohno said that in mammals, natural selection could only cope with a limited number of harmful mutations without being swamped, with deterioration and extinction as the result. He estimated that, given known rates of mutation, a maximum of 30,000 genes could be subject to selection. This makes intuitive sense – even under the best circumstances how could the environment select the best combination of hundreds of thousands of finely varying … Continue reading →