The Quest for Designer Children
determinism. Some diseases are linked to a single gene, such as TaySachs. For these diseases, we have made(and will continue to make) great strides in identifying the gene and the incorrect coding sequence (more precisely, a wrong allele) in the gene.
Most of the associations between genes and our health are, however, more complex, involving a combination of many genes often in hard-to-fathom interactions. Even if we master these complexities and engineer people with genes not only for longevity but also for a reduced susceptibility to physical illness and mental decline, most diseases are multifactorial, that is, they result from a combination of genetic, dietary, and environmental factors. Many ailments, such as lung cancer, arise from genes interacting with environmental influences. Unless environmental improvements are also undertaken, a 120-year life span may be a more realistic maximum age for most of us. Nongenetic and nonenvironmental factors, such as chance events, also play a role in good health and longevity.
Whether we live 80 or 150 years, the question remains: how will each of us use our years? Will we lead different, better, more productive lives with more vital years to contribute? Will we be concerned with guiding the generations that follow us and passing on our acquired wisdom, values, and awareness?
Despite our best efforts, earthly life will remain finite. Life will still gain value knowing we have limited time and resources on earth before we die. Our finiteness will continue to force each of us to focus our time and energy on what is important in our life.
NON-THERAPEUTIC GENETIC ENGINEERING
Genetic procedures may serve nontherapeutic purposes, improving human appearance, functioning, or performance, beyond what is needed to restore or sustain good physical and mental health. Genetic testing may be used to screen and abort“defective” fertilized eggs, embryos, and fetuses manifesting“undesirable” traits or