Drawing a line: Situating moral boundaries in genetic medicine

Bioethics traditionally focuses orb establishing moral limits between diffe rent types of acts. However, boundaries are established by communities and individuals who differ in the constraints shaping their moral world. Phase bo boundaries, the sites of transition between. two physical phases such as a liquid and a gas, provide a metaphor for 'drawing a line' ist bioethics discourse. Phase boundaries occur where the physical constraints allow both phases to coexist in stable equilibrium. This relationship carl also be co nsidered in reverse, using the known position of the phase boundary to disc lose the physical constraints, By analogy, instead of trying to locate the 'correct' moral boundary, the alternative perspective of 'reverse ethics' w orks from a commonly accepted boundary to examine the constraints of the mo ral world that are being used to establish it. Genetic interventions into t he human. body provide interesting examples of boundary establishment. In g ene therapy, focusing on boundaries has resulted in a model of moral permis sibility that ignores some alternative standpoints and increases the potent ial for conflict between them, Reverse ethics examines such conflicts in te rms of the nature of the moral worlds that have come into contact with each other, taking seriously tile diversity of factors governing the location o f a boundary, in ways that might help shift some entrenched lines of confli ct.