Genetic enhancement refers to the use of genetic engineering

Genetic engineering

Genetic engineering, also called genetic modification, is the direct human manipulation of an organism's genome using modern DNA technology. It involves the introduction of foreign DNA or synthetic genes into the organism of interest...

 to modify a person's nonpathological

Pathology

Pathology is the precise study and diagnosis of disease. The word pathology is from Ancient Greek , pathos, "feeling, suffering"; and , -logia, "the study of". Pathologization, to pathologize, refers to the process of defining a condition or behavior as pathological, e.g. pathological gambling....

 human traits. In contrast, gene therapy involves using genetic engineering to alter defective genes

Gênes

Gênes is the name of a département of the First French Empire in present Italy, named after the city of Genoa. It was formed in 1805, when Napoleon Bonaparte occupied the Republic of Genoa. Its capital was Genoa, and it was divided in the arrondissements of Genoa, Bobbio, Novi Ligure, Tortona and...

 or insert corrected genes into the body in order to treat a disease

Disease

A disease is an abnormal condition affecting the body of an organism. It is often construed to be a medical condition associated with specific symptoms and signs. It may be caused by external factors, such as infectious disease, or it may be caused by internal dysfunctions, such as autoimmune...

.

Enhancement versus therapy

There is no clear distinction between genetic enhancement and gene therapy

Gene therapy

Gene therapy is the insertion, alteration, or removal of genes within an individual's cells and biological tissues to treat disease. It is a technique for correcting defective genes that are responsible for disease development...

. However, whether a genetic modification procedure is deemed to be one of enhancement or therapy could affect its degree of accessibility, as therapeutic procedures are more likely to be covered by insurance

Insurance

In law and economics, insurance is a form of risk management primarily used to hedge against the risk of a contingent, uncertain loss. Insurance is defined as the equitable transfer of the risk of a loss, from one entity to another, in exchange for payment. An insurer is a company selling the...

.

One approach to distinguishing between the two is to classify any improvement beyond that which is “natural” as an enhancement. “Enhancement” would then include preventive measures such as vaccines, which strengthen one’s immune system

Immune system

An immune system is a system of biological structures and processes within an organism that protects against disease by identifying and killing pathogens and tumor cells. It detects a wide variety of agents, from viruses to parasitic worms, and needs to distinguish them from the organism's own...

 to a point beyond that which would be achieved “naturally.”

Another approach is to consider therapy as encompassing any process aimed at preserving or restoring “normal” functions, while anything that improves a function beyond that which is “normal” would be considered an enhancement. This, however, would require “normal” to be defined, which only frustrates the clarification of enhancement versus therapy.

Yet another way to distinguish between therapy and enhancement might rely on the goal of the genetic alteration. But the classification of the goal will necessarily depend on how “disease” or “normal” is defined.

Genetic enhancement in humans

If genetic enhancement is defined such that it includes drugs that are made with genetic knowledge or using rDNA techniques, then forms of genetic enhancement are already in use. Parents seek human growth hormone

Growth hormone

Growth hormone is a peptide hormone that stimulates growth, cell reproduction and regeneration in humans and other animals. Growth hormone is a 191-amino acid, single-chain polypeptide that is synthesized, stored, and secreted by the somatotroph cells within the lateral wings of the anterior...

 for their healthy, non-growth hormone deficient

Growth hormone deficiency

Growth hormone deficiency is a medical condition in which the body does not produce enough growth hormone . Growth hormone, also called somatotropin, is a polypeptide hormone which stimulates growth and cell reproduction...

 short children in hopes of improving the children’s self-esteem

Self-esteem

Self-esteem is a term in psychology to reflect a person's overall evaluation or appraisal of his or her own worth. Self-esteem encompasses beliefs and emotions such as triumph, despair, pride and shame: some would distinguish how 'the self-concept is what we think about the self; self-esteem, the...

. Some athletes use erythropoietin

Erythropoietin

Erythropoietin, or its alternatives erythropoetin or erthropoyetin or EPO, is a glycoprotein hormone that controls erythropoiesis, or red blood cell production...

, a hormone

Hormone

A hormone is a chemical released by a cell or a gland in one part of the body that sends out messages that affect cells in other parts of the organism. Only a small amount of hormone is required to alter cell metabolism. In essence, it is a chemical messenger that transports a signal from one...

 that regulates red blood cell

Red blood cell

Red blood cells are the most common type of blood cell and the vertebrate organism's principal means of delivering oxygen to the body tissues via the blood flow through the circulatory system...

 production, in efforts to improve their performance.

Using the results of genetic tests to make reproductive decisions based on non-disease traits could be considered to be a form of passive genetic enhancement. Those seeking to create an “enhanced” child could simply turn down potential mates who do not exhibit the desired advantages. Likewise, selectively aborting

Abortion

Abortion is defined as the termination of pregnancy by the removal or expulsion from the uterus of a fetus or embryo prior to viability. An abortion can occur spontaneously, in which case it is usually called a miscarriage, or it can be purposely induced...

 fetuses after performing an in utero

In utero

In utero is a Latin term literally meaning "in the womb". In biology, the phrase describes the state of an embryo or fetus. In legal contexts, the phrase is used to refer to unborn children. Under common law, unborn children are still considered to exist for property transfer purposes.-See also:*...

 test could be categorized as a type of enhancement technique.

Gene transfer

Horizontal gene transfer

Horizontal gene transfer , also lateral gene transfer , is any process in which an organism incorporates genetic material from another organism without being the offspring of that organism...

 experiments in animals have so far failed to produce results that would justify performing gene transfer in humans; however, gene transfer techniques may eventually be used for enhancement purposes. Gene transfer can be used to modify either somatic

Somatic cell

A somatic cell is any biological cell forming the body of an organism; that is, in a multicellular organism, any cell other than a gamete, germ cell, gametocyte or undifferentiated stem cell...

 or germ-line cells  Gene transfer approaches involving the early embryo

Embryo

An embryo is a multicellular diploid eukaryote in its earliest stage of development, from the time of first cell division until birth, hatching, or germination...

 are presently far more effective than somatic cell gene therapy methodologies, which may result in “random integration of donor DNA

DNA

Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...

, a lack of control of the number of gene copies inserted, significant rearrangements of host genetic material, and a five to ten percent frequency of insertional mutagenesis

Insertional mutagenesis

Insertional mutagenesis is mutagenesis of DNA by the insertion of one or more bases.Insertional mutations can occur naturally, mediated by virus or transposon, or can be artificially created for research purposes in the lab.- Signature tagged mutagenesis :...

.” In general, however, the use of gene transfer techniques to modify a phenotypic trait will likely be unsuccessful. Hundreds of genes may play a role in any expressed phenotype; and gene transfer attempts to modify only specific loci in isolation.

Somatic gene transfer will not result in a heritable

Heritability

The Heritability of a population is the proportion of observable differences between individuals that is due to genetic differences. Factors including genetics, environment and random chance can all contribute to the variation between individuals in their observable characteristics...

 genetic modification. Germ-line gene transfer, on the other hand, will produce transmittable genomic changes.

Concerns regarding genetic enhancement

A number of concerns are raised by genetic enhancement. The concerns are based on ideas of equality and fairness, as well as philosophical and religious arguments.

The Undermining of the Principle of Social Equality

An issue that arises in the context of genetic enhancement is the provision of equal access to genetic enhancement technologies. The high cost of genetic enhancement could prevent all but the wealthy from gaining access to enhancement procedures. Wealth-based genetic enhancement could create a social hierarchy, with those who can afford enhancement gaining power over the unenhanced. If individuals are enhanced by the use of germ line modifications, then the enhancements will be passed on to offspring

Offspring

In biology, offspring is the product of reproduction, of a new organism produced by one or more parents.Collective offspring may be known as a brood or progeny in a more general way...

, who would then pass the enhanced genes to their offspring, and so on. This would create a division between those who are enhanced and those who are not. To the extent that the enhancements made individuals more successful, enhanced individuals would likely gain power over those who cannot afford enhancement procedures.

The creation of an unfair advantage

Distributive justice

Distributive justice

Distributive justice concerns what some consider to be socially just allocation of goods in a society. A society in which incidental inequalities in outcome do not arise would be considered a society guided by the principles of distributive justice...

 notions issues would arise, as the net effect of genetic enhancement procedures felt by those who could afford such procedures would likely be less than the benefit that would be perceived by those who cannot afford genetic enhancement procedures. The costs associated with the procedures would make it difficult to provide access to those who are naturally the least advantaged.

Evolutionary concerns

There is some concern that genetic enhancement could affect human evolution

Evolution

Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...

. In response, geneticists have pointed out that human evolution will likely be unaffected, because evolution results from a nonrandom change in allelic frequencies

Allele frequency

Allele frequency or Gene frequency is the proportion of all copies of a gene that is made up of a particular gene variant . In other words, it is the number of copies of a particular allele divided by the number of copies of all alleles at the genetic place in a population. It can be expressed for...

 due to selective pressure

Evolutionary pressure

Any cause that reduces reproductive success in a proportion of a population, potentially exerts evolutionary pressure or selection pressure. With sufficient pressure, inherited traits that mitigate its effects - even if they would be deleterious in other circumstances - can become widely spread...

. Individuals with certain patterns of alleles are favored reproductively, so any introduction of new alleles by gene transfer would have a negligible effect on the species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

.

Additionally, it is not clear that the phenotypes of genetically enhanced individuals would be those that lend themselves to greater reproductive success

Reproductive success

Reproductive success is defined as the passing of genes onto the next generation in a way that they too can pass those genes on. In practice, this is often a tally of the number of offspring produced by an individual. A more correct definition, which incorporates inclusive fitness, is the...

.

Furthermore, any genetic modification that does not affect germ cells will not be transmitted to offspring. On a related note, regardless of whether the enhanced genes themselves are actually passed on, evolution in memes may occur if genetic modification of parents improved the unmodified offspring's fitness

Physical fitness

Physical fitness comprises two related concepts: general fitness , and specific fitness...

 and propagated the behavioral tendency to genetic enhancement.

Philosophical or religious objections

Some critics have raised arguments against genetic enhancement based on the idea that humans engaging in genetic enhancement would be overstepping their bounds by “playing God” and intervening in fundamental biological processes.

Genetic enhancement procedures may result in a reduction in the general feeling of social solidarity

Social capital

Social capital is a sociological concept, which refers to connections within and between social networks. The concept of social capital highlights the value of social relations and the role of cooperation and confidence to get collective or economic results. The term social capital is frequently...

 or goodwill. Assuming that people recognize that their talents that contributed to their successes are due to a “gift” of good genes rather than hard work, they may feel obligated to share the rewards of their genetic gifts with those less fortunate. People may be less likely to share the benefits of their genetic advantages, however, if they no longer attribute their talents and successes to good fortune.
On the other hand, the behaviors of genetically enhanced humans may be unpredictable. Individuals may even become misanthropic due to the feeling that they are mutants that were created in a test tube. It is hypothesized that watching movies such as Gattaca or Frankenstein may result in depression among genetically enhanced humans.

Regulating access to genetic enhancement

In general, most countries do not regulate the ability of those who are naturally talented to further enhance certain characteristics. People who naturally excel at sports, for example, are not prohibited from training and further improving their athletic abilities; and children with above average capacities for learning are routinely placed in honors or accelerated academic programs. Perhaps because such inequalities are perceived as being the result of innate talents or abilities, we are willing to tolerate these differences.

Genetic enhancement is considered morally contentious, however, and access to enhancement procedures will likely be regulated. Possible regulatory schemes include a complete ban of genetic enhancement, provision of genetic enhancement procedures to everyone, or a system of professional self-regulation.

Banning all genetic enhancement procedures would keep wealthy people from using genetic enhancements to gain power over unenhanced individuals; however, preventing individuals from illegally obtaining genetic enhancements may be difficult. Preventing people from engaging activities that they would otherwise pursue would also raise issues of fairness.

Making genetic enhancement procedures available to everyone might be the most fair, but it could also be extremely costly; and some individuals would inevitably choose not to undergo enhancement procedures. Hence, this regulatory scheme could result in the same classes of enhanced and unenhanced individuals that would be expected if there were no regulation.

Perhaps the most practical regulatory approach is the self-regulation of health professionals. The American Medical Association

American Medical Association

The American Medical Association , founded in 1847 and incorporated in 1897, is the largest association of medical doctors and medical students in the United States.-Scope and operations:...

’s Council on Ethical and Judicial Affairs has stated that “genetic interventions to enhance traits should be considered permissible only in severely restricted situations: (1) clear and meaningful benefits to the fetus or child; (2) no trade-off with other characteristics or traits; and (3) equal access to the genetic technology, irrespective of income or other socioeconomic characteristics.”