We No Longer Have Eugenics Laws, but How Might Genetic

We no longer have eugenics laws, but how might genetic therapies and screening be used to similar effect (to enhance the "human stock") ?

A) If genetic screening is done on everyone, we'll know who has criminal or other defective tendencies and be able to prevent them from reproducing unless we "fix" their genes.
B) If all embryos are screened for defects, parents will have the option of getting them fixed or terminating the pregnancy, such that only good quality people are born.
C) If the government has access to our DNA, they can decide what defects preclude reproduction and create new laws.
D) If all potential parents get genetic screening, those found to have defective genes could be prohibited from reproducing.
E) If all parents are screened for genetic defects, their genes can be fixed before they try to have children.