Observing insane existence! An argument for eugenics ?

The film strikes me as existentialist to its core. The boy observes and is surrounded by an insane world. His father is an ignorant, bowl-obsessed ape, his sisters are severe mental retards, his grandfather is a catatonic maniac, his brother is a low-IQ big muscle wimp and his mother is a primordial oversized and overprotective cave-woman. Only he seems to possess a spark in his eyes and intellectual curiosity. He would've made a good naturalist had he gone to college, instead he is a ghetto "naturalist". At the end though boy's grandpas deleterious genetic endowment (which might had resulted from inbreeding) coupled I guess with a desperate environment, brings him in to a psychiatric state of no return. Then is this a strong argument for not only improving quality of life in poor neighborhoods, but also quality of genotype, perhaps through eugenic methods like selective in-vitro-fertilization and human cloning ?