Effect of environment of genes is called -

Effect of environment of genes is called euthenics studies with mentally retarded children indicated that exposure to environmental stimulation improved their IQ negative eugenics is to reduce the frequency of hereditary disease and disability in the community by sterilisation or debarration of patients from producing children in positive eugenics , improve the genetic composition by encouraging the carriers of desirable genotypes to assume the burden of parenthood ref; (page no;828) 23rd edition of PARK&;s textbook of Preventive and Social medicine