 Instead, these models predict that neutral variation is correlated with the selective pressures acting on linked non-neutral genes, that neutral traits are not necessarily oblivious to selection.Because they segregate together, non-neutral mutations linked to neutral polymorphisms result in decreased levels of genetic variation relative to predictions of neutral evolution.The reduction in neutral variation due to background selection can be modeled by an exponential function of the total mutation rate at the deleterious regions of the section of genome involved.