The idea of the perfect human has been around a long time. From Tao Te Ching to Nietsche and Galton, many great minds have described certain desirable and non-desirable qualities of man. Until recently, all human reproduction resulted from sexual intercourse, and couples had to be prepared for the luck of the natural lottery. Now powerful new technologies are changing the reproductive landscape and challenging basic notions about procreation, parenthood, family, and children. Recent scientific discoveries within the field of human genetics and reproductive technologies have revitalized many timeless thoughts about human perfection.
PGD, or preimplantation genetic diagnosis marries the recent advances in molecular genetics and assisted reproductive technology. Preimplantation genetic diagnosis enables physicians to identify genetic diseases in the embryo, prior to implantation, before the pregnancy is established. PGD obviate the need for screening during a pregnancy and hence prevent the physical and psychological trauma associated with possible termination.
Every person or couple contemplating children wants healthy offspring, yet knows that offspring characteristics cannot be guaranteed in advance. New screening and selection technologies are now changing this situation. Prenatal diagnosis is occurring earlier and for a wider range of conditions. In the future techniques to alter genes for both therapeutic and nontherapeutic purposes will become available. Whether couples may or must use these techniques raises important questions about the scope of procreative liberty.
Selection techniques now rely on carrier or prenatal screening to identify persons at risk for having handicapped offspring. Today carrier screening mostly occurs in high-risk subgroups, but will eventually touch most couples, as carrier tests for cystic fibrosis and other common conditions become routinely available. Couples aware of their carrier status may then decide not to reproduce, use donor gametes, or adopt. They may also seek prenatal diagnosis and terminate pregnancy if they do conceive. As the ability to diagnose more genetic conditions earlier and less invasively grows, prenatal screening will eventually affect most pregnancies.
PGD was first used in the early 1990s to screen out embryos carrying the mutations that cause inherited diseases such as Duchenne’s muscular dystrophy. The clinics offering it as a way of improving pregnancy rates look instead at whether the right number of chromosomes is present. About one per cent of embryos from women in their 20s and early 30s are aneuploid, in women over 40 the figure is over 50 per cent.
As tests to identify fetal cells in maternal blood are perfected, the genetic condition of every fetus will be diagnosable at 7–8 weeks by a simple blood test. It is likely that such tests will become a routine part of prenatal care, followed often by pregnancy termination when the test is positive. Genetic diagnosis of preimplantation embryos, now occurring in clinical experiments, will also be available. (See “Children of Choice: Freedom and the New Reproductive Technologies”, Assisted Reproduction.)
Edwards and Gardner successfully performed the first known embryo biopsy on rabbit embryos in 1968. In humans, PGD was developed in the United Kingdom in the mid 1980s as an alternative to current prenatal diagnoses. PGD is presently the only option available for avoiding a high risk of having a child affected with a genetic disease without facing the dilemma of pregnancy termination following positive prenatal diagnosis. In 1989 in London, Handyside and colleagues reported the first unaffected child born following PGD performed for an X-linked disorder. As of May 2001, more than 3000 PGD clinical cycles have been reported. These cycles were performed at more than 40 centers around the world, and almost 700 children have been born, thus demonstrating the reliability and safety of the procedure.
Couples who elect to have PGD undergo an in vitro fertilization (IVF) embryos are formed as usual in the laboratory. Embryos are then biopsied with very fine glass needles and tools under microscopic observation and control to obtain one or two sample cells (blastomeres) for genetic analysis using either specialized DNA amplification or fluorescent hybridization systems. Embryos whose biopsy results are normal are then available for immediate transfer into the uterus, with additional embryos (if available) frozen for subsequent transfer. Experiences with PGD in humans have documented the safety and efficacy of this technology for preventing genetic disorders and producing the births of normal children.
Current uses of PGD range from sex selection (family balancing or as a stem cell source) and ensuring that inherited diseases are avoided. PGD can be offered for 3 major groups of disease, including (1) sex-linked disorders, (2) single gene defects, and (3) chromosomal disorders. Down Syndrome, X-linked diseases (Duchenne Muscular Dystrophy), chromosomal translocation, Spinal Muscular Atrophy, Tay Sachs Disease, Hemophilia, Huntington Disease and Cystic Fibrosis and many other genetic diseases can be avoided using PGD.
Demographic Consequences of Reproductive Technologies
The reasons for selecting the sex of your child vary. The Chineses one-child policy has caused a major market for sex selection services. The effects of such policies on the demographic characteristics of the population cause controversy. Since the male population is associated with higher income and living standards many opt for male children. The resulting male/female imbalanced ratio could cause massive emmigration of Chinese males looking for females elsewhere.
In the West potential parents choose the sex of the children based on so-called “family balancing” rethoric. Ensuring that you have both male and female kids is by many considered vanity. Parents have used sex-selection to produce donor kids for their existing kids with an organ-disorder. Many of these advances become precedent for future applications of reproductive technologies.
People with inherited diseases often learn to live with the disability and accept imperfect genetics as a part of life. Blind parents have chosen to ensure that their offspring also will be blind. Accepting the genetic diversity of mankind is essential to an ethical approach to reproductive technologies. Accepting differences in humans doesn’t bother most people when they try to ensure healthy kids. The slippery slope of reproductive technologies starts where “ensuring healthy kids” ends and “human enhancement” begins.
From the Oneida Community to Transhumanism
John Humphrey Noyes lead the human selective breeding programme taking place in a North American bible communist community, Oneida, between 1869 and 1879. It was probably the first such breeding experiment of the modern era, and for this reason, we might expect it to have been influential for the subsequent eugenics movements. Although it attracted much attention in its day, its longer-term influence seems to have been surprisingly slight, largely because its specific context meant that it was not a model that provided an acceptable way to reach eugenics goals. (See “A Nineteenth-Century Experiment in Human Selective Breeding”, Nature 2004)
The idea of the Oneida Community was to breed superior children by encouraging the mating of the healthiest, most intelligent males and females. After much debate, Noyes had become convinced that “a scientific breeding program could be adapted to the needs of the Oneida community” (Kephart and Zellner, p.84). This practice of stirpiculture, then, can be regarded as a derivation of the principle of eugenics — attempts to improve hereditary qualities; selective breeding. Although no such term was known at the time of the Community, this is exactly the concept that Noyes and his people adopted. Only certain people were allowed to become parents, and these were hand-picked by a special committee. Nearly ninety percent of Community babies born in an eleven-year span were carefully planned by such a committee. During the time of the program, no defective children were born, and no mothers died as a result of childbirth. (See “The Oneida Community”, Religious Movements).
Similar ideas are presented in Galton’s “The University of Kantsaywhere”. Pearson (1930, pp. 411 ff.) has published the surviving fragments of Kantsaywhere, a short utopian novel Galton wrote in 1910, just before he died. In this fantasy, a young Englishman finds himself in “Kantsaywhere,” a country that has instituted highly effective eugenic practices. Preeminent among these are two examinations administered by the local “Eugenic College.” First is a largely medical “Pass Examination” which must be taken by everyone and passed to gain State permission to marry and have children. A sufficiently high pass on this entitles one to compete in the further “Honours Examination,” with four equally weighted parts measuring a) medical fitness; b) ancestral quality; c) anthropometric quality; and d) aesthetic and literary skill. The anthropometric tests in this examination are exactly like those from the South Kensington Laboratory. The “aesthetic and literary” section includes assessment of aesthetic judgment, as well as more standard examination tasks such as essay writing.
To imagine a modern Oneida Community or University of Kantsaywhere is a challenging task. People today are used to genetic tests and family planning. The basis for a new eugenics movemement should be individual freedom of choice. The development of more powerful reproductive technologies speed up the possibilites of human enhancement. If parents were given the option to select for cognitive capabilities, height, hair and eye color, strength and other phenotypical features – do you think they would choose not to use it?
Transhumanists promote the view that human enhancement technologies should be made widely available, and that individuals should have broad discretion over which of these technologies to apply to themselves (morphological freedom), and that parents should normally get to decide which reproductive technologies to use when having children (reproductive freedom). Transhumanists believe that, while there are hazards that need to be identified and avoided, human enhancement technologies will offer enormous potential for deeply valuable and humanly beneficial uses.
“Ultimately, it is possible that such enhancements may make us, or our descendants, “posthuman”, beings who may have indefinite health-spans, much greater intellectual faculties than any current human being – and perhaps entirely new sensibilities or modalities – as well as the ability to control their own emotions.” (See “In Defense of Posthuman Dignity”, Nick Bostrom)
Death as Curable Disease
Aging is a three-stage process: metabolism, damage, and pathology. The biochemical processes that sustain life generate toxins as an intrinsic side effect. These toxins cause damage, of which a small proportion cannot be removed by any endogenous repair process and thus accumulates. This accumulating damage ultimately drives age-related degeneration. Interventions can be designed at all three stages.
However, intervention in metabolism can only modestly postpone pathology, because production of toxins is so intrinsic a property of metabolic processes that greatly reducing that production would entail fundamental redesign of those processes. Similarly, intervention in pathology is a “losing battle” if the damage that drives it is accumulating unabated. By contrast, intervention to remove the accumulating damage would sever the link between metabolism and pathology, and so has the potential to postpone aging indefinitely. We survey the major categories of such damage and the ways in which, with current or foreseeable biotechnology, they could be reversed. Such ways exist in all cases, implying that indefinite postponement of aging–which we term “engineered negligible senescence”–may be within sight. Given the major demographic consequences if it came about, this possibility merits urgent debate. (See “Critiquing the immutability of human aging”, PubMed)
Understanding and manipulating the genetics of aging would also cause enormous consequences. If aging is caused by a set of genes and these genes were to be found the ability to re-set the “death-clock” would be very tempting. Gene therapy on adults or genetically modified kids with expected life spans of, say, 200 would cause incredible consequences on pensions, insurance and other vital parameters of modern life.
Stem Cells and Gene Therapy
Human stem cell lines from genetically flawed human embryos have been created by US scientists. The team that produced the mutant lines at the Reproductive Genetics Institute in Chicago believes the cell lines will help shed light on genetic diseases and could be used to test new treatments.
The team is the first to announce the creation of human embryonic stem cell (ESC) lines from embryos with specific genetic diseases, However, other groups around the world have also been racing to develop mutant ESCs, one group in the UK has already created a line for cystic fibrosis.
The US cell lines were produced from embryos left over from in-vitro fertilisation procedures. The embryos were discarded after genetic screening revealed they had defects. The immortal lines generated include several for diseases caused by single gene mutations, including some muscle and blood disorders. (See “Mutant human stem cell lines created”, New Scientist)
Establishment of embryonic stem cells derived from mutant embryos provides new opportunities for studying and treatment of human genetic disorders, gene therapy, pharmaceutical development and toxicological screening technologies. Stephen Minger, director of the stem cell biology laboratory at King’s College London, UK, agrees that such mutant ESCs could help scientists better understand certain diseases and test treatments. But he adds each line will have “greater or lesser merit” depending on the disease.
Saving the World with Genetic Enhancement
As biomedical science progresses, ever more effective medical technologies are devised for the treatment of illnesses, and this is, of course, a good thing. But how do we feel about the use of such technologies by people who are healthy to start with in order to become more than healthy? Many such enhancement technologies are already widely available. Cosmetic surgery is used for aesthetic enhancement of the body, beta-blockers such as Propranolol by musicians to block the physical symptoms of performance nerves, thereby enhancing the quality of their playing, and the antidepressant Prozac is used as an agent of what Peter Kramer has called cosmetic psychopharmacology, or alteration of personality, to make people less shy, less compulsive, more confident. We have to assume that with time more enhancement technologies will become available – many more, employing surgery, genetics, pharmacology, and heaven knows what else, directed in particular at cognitive function and longevity. (See “Enhancing human Traits: Ethical and Social Implications”, Nature 1999)
Further advances within biotechnology, gene therapy, genetic engineering, stem cells and PGD will cause massive demographic changes. People would live longer, healthier and more intelligence lives. People would be able to have multiple educations and multiple careers and would thus become more knowledgeable and experienced than contemporary humans. This will lead to better problem solving and more efficient organizations, and subsequently the possibilty of ending war, hunger and diseases. The final reasonable exit left for mankind out of the mess we call earth, is through genetic enhancement.
When the genetics of intelligence (g, or General Intelligence) is understood parents would face the dilemma of choosing to live with a brighter kid than themselves. The difference between “high-investement parenting” and “high-intelligence parenting” could change. Society would have to undergo a dramatic change of the perception of human qualitities. New lines of work would ensue after a generation of high-intelligence parenting. New types of schools and new communities would naturally follow in the wake of widespread genetic enhancement of humans.
A new debate and a subsequent new ethics for the evolution of humans is of critical importance for the survival of modern civilization.