Dan Graur, Professor of the Department of Biology & Biochemistry at the University of Houston and author of the study, told Radio Sputnik that his research was based on the work of the late Herman Muller, geneticist and Nobel laureate who created the concept of the mutation load.
"The mutation load essentially means that every functional part in your body or in your genome can experience changes that will be bad for them. Like in life, every functional entity, if left unchecked, will deteriorate and cease working – you cannot leave your television on and expect that in a million years it will still work. The enemies of genes are mutations, and the vast majority of mutations that happen in the functional portion of the genome are deleterious," he explained.
According to Graur, humanity overcomes this problem by “making more children to replace the population size”, thus compensating for the loss of people who die before reaching the reproductive age.
"Now if the entire genome is functional, the number of deleterious mutations would be so great that it would require each person in the world to have more children than there are galaxies in the universe… So the only escape from this mutation load paradox is to assume that not the entire genome is functional, and according to my calculations based on mutation rate and population size and genome size, the maximum that is possible to be functional is about 25 percent, more reasonably in-between 10 and 15," Graur said.
He also remarked that while his research is about "basic science" and that he doesn’t care about its practical application, the study serves as proof that "our genomes are the product of evolution."
"The main impact of this study is to show that our genomes are the product of evolution and not designed by an intelligent designer, because no intelligent designer would make anything so badly designed," Graur explained.
However, it also appears that it is this very large amount of junk DNA within our genome is what makes us human, the scientist remarked.
"I suppose that if everything was functional, first of all we wouldn’t be human, so we would be something more similar to bacteria. We would be able to multiply very rapidly and be able to sustain mutations. The only human who would have a 100-percent genome will be one in which mutations do not occur," Graur said, adding that it is unlikely to happen during his lifetime.