||Harris 1992 argues that it is mandatory to use advances in gene therapy to remove vulnerability to infections and pollutants or to radiation damage. It advances an argument that, beside removing the genetic causes of what we regard today as "disability", it is equally mandatory to retard the ageing process, remove predispositions to heart disease, destroy carcinogens and permit human beings to tolerate other environmental pollutants. Buchanan et al 2000 focuses on justice in the access to human genetic technology, but considers a broad range of themes and arguments: the moral heredity of eugenics, the distinction between therapy and enhancement, constrains and permissions on parental choices of genetic selection, and the disability critique of liberal eugenics. It maintains a position that is liberal, in that it permits individuals a wide range of choices concerning the genetic endowments of their future children, yet constrains it by blocking interventions which would harm the future person (by reducing future options) or society (by causing an unfair distribution of social goods). Fukuyama 2002 regards genetic technology the practice that will radically change human nature with irreversible moral implications. Genetic technology is thus objectionable, in that undermines the natural presuppositions of egalitarian liberalism. Habermas 2003 defends a principled distinction between gene-therapy to cure disease and genetic manipulation allowing parents to select the traits of future children. The latter is seen as incompatible with egalitarian relationships between human beings and their freedom of choice.