Genetic engineering is a new science and so there is no direct guidance from scripture. In forming their views on the various types of genetic engineering and gene therapy, Buddhists would draw on the following religious concepts and beliefs.
He who for the sake of happiness hurts others who also want happiness, shall not hereafter find happiness.Dhammapada 131
Buddhists find other guidance in the Noble Eightfold Path. The two aspects of the Noble Eightfold Path that are of particular relevance to gene therapy and genetic engineering are Right Action and Right Livelihood.
The two related concepts of karuna and metta will also guide Buddhists when they are making decisions concerning genetic engineering and gene therapy. The Buddha taught that Buddhists should relieve suffering and said:
Whoever, O monks, would nurse me, he should nurse the sick.Buddha
As with all people considering whether the different types of genetic engineering and gene therapy are right, a Buddhist will consider the short and long-term benefits and risks of each process. As on many other issues, how each teaching is interpreted and applied may differ within and between different Buddhist traditions and individual Buddhists.
Buddhists will attempt to apply upaya kausalya when making their personal decision on gene therapy and genetic engineering.
An important consideration is how an individual Buddhist understands causality (that everything has a cause). Buddhist believe in karma or 'intentional action'. If they think that things occur for a variety of reasons besides previous actions, then they are more likely to think that interventions that prevent suffering are good. This is because an illness could be a morally neutral experience.
But if they believe that everything comes about because of previous actions then they might argue that the suffering they experience now is working off the result of former bad actions which have to be experienced sometime. However, almost every Buddhist would choose to support actions that reduce suffering.