Thus, the initial gene frequency of 0.0071 will be reduced to about 0.004152 and the number of carriers by about 41% to 1/121 in about 3,000 years. Also, behavioral traits are under the control of multiple genes, scattered in the genome, and each of them contributes partly to the phenotype. Furthermore, characters as these are under polygenic control and are greatly affected by environmental influences. Thus, the negative eugenic measures are biologically ineffective and ethically unacceptable in enlightened societies. Nevertheless, in the name of eugenics, Hitler’s regime exterminated six million Jews and millions of others of different ethnic groups, as well as sterilized more than 250,000 people. Negative eugenics, although it is quite ineffective as shown above, still may have some justification in some forms chosen by the individuals at high genetic risk of disease. The simplest humane and intellectually and ethically correct solution is refraining from reproduction. Therapeutic abortion is counterproductive because it may increase the number of carriers although the “defective” individuals (homozygotes) are eliminated.

Positive eugenics has some biological and ethical problems too because human values cannot be adequately assessed. Certain measures may, however, be acceptable and are practiced in societies without naming them as eugenics. For example, adequate scholarship to college students may facilitate their support of a family and thus, presumably, intellectually better individuals may not be prevented from procreation because of economic hardship. Also, reproduction at a younger age may reduce chromosomal defects (see  Down’s syndrome). The Nobel-laureate geneticist H. J. Muller advocated positive eugenics throughout his career. He considered it a necessity to fight genetic load through germinal choice, meaning that spousal love should be separated from procreational role in marriage. He suggested the reliance of gene banks for artificial insemination of the women and recommended systematic screening of the sperm donors on the basis of health, intellect, and social consciousness. The sperm of the selected individuals were supposed to be stored frozen and used only some years after their death to make an objective and reliable assessment of their value. Although such a program may appear reasonable, problems in value judgment remain. Muller believed that in a true socialist political and social system these problems could be overcome. His own disenchantment with the Marxist society of the USSR proved, however, otherwise. Some general fears of intervention in the human system of reproduction are still not completely dissolved. Will the controlled insemination reduce the gene pool? Is it conceivable that the selection may foster the increase of some so far unforeseen genetic defects either by lack of recognition or by hitchhiking (linkage)? Is there a risk that political systems impose their selfish will upon the biologically desirable systems of reproduction? The problems of positive eugenics may not, however, be ignored. The progress in medical technologies prevents the selection against formerly inferior traits. The uses of medication, prosthetics, somatic gene therapy, etc., are devices of contraselection. Perhaps, the replacement of genes of the germline involved in clinically proven defects may offer a solution. The methodology now appears clear in principle, but the consequences are still untested. Thus, the “brave new world” is not yet at hand, primarily because our values cannot be defined in a simplistic manner. Eugenics must be separated from the racist views that discredited the field. Multiracial and multicultural societies offer unique advantages in their diversities for the betterment of life. Biologists must find the facts but the application of the principles discovered requires the democratic decisions of the ethicists and the societies. Will ethicists know enough biology?  gene therapy,  eutelegenesis,  Hardy-Weinberg theorem,  sterilization in humans,  genetic counseling,  Galtonian inheritance; Kempthorne O 1997 Genetica 99:109; Li CC 2000 Hum Hered 50:22; Micklos D, Carlson E 2000 Nature Rev Genet 1:153; Gillham NW 2001 Annu Rev Genet 35:83; a historical display on origin and flaws: http://www.galton.org/; http://vector.cshl.org/.