Part 2 – Human augmentation technologiesGenetic engineering
Genetic engineering refers to modification of reproductive cells (germline engineering),
or cells in the grown organism (somatic modification). Germline modification affects
all cells in the organism and the change is passed on to the next generation. Somatic
modification affects only the target cells and those cells descended from them in
the body, hence is limited to the individual being treated. Genetic engineering has
been around for some time but has so far been limited to relatively crude and simple
modifications, often involving just one or two genes.
Creating genetically modified humans has been widely considered unacceptable for many
years and is formally prohibited in over 40 countries, but there are signs that this stance
is being challenged by the advent of new technologies. For example, the development
in 2012 of a technique called clustered regularly interspaced short palindromic repeats
(CRISPR) provides a set of ‘molecular scissors’ that are cheaper, faster and more
accurate than previous methods of genetic editing. In 2019, CRISPR was used to treat a
blood disorder in the first somatic modification of a person. The year 2020 will see further
trials to restore sight in patients suffering from an inherited eye disorder. This and other
recent developments are beginning to offer significant potential for a number of reasons.
a. Greater range. Gene editing can now add, delete or alter specific elements of
DNA in the target genome. CRISPR can create multiple changes at once.b. Increased specificity and integration. Specific regions of DNA can be targeted
by cutting tools so that changes are more precise and safer. There are still off-target
effects but newer techniques such as prime editing are improving the targeting
process.c. Improved duration of effect. Being able to target the genome rather than
simply depositing DNA into cells means that edits are reproduced as the cell divides
and the effect is promulgated.d. Easier production. New production techniques are often easier, cheaper and
faster to develop and perform.^12Future opportunities. Genetic engineering could be used to prevent people from
inheriting incurable diseases or traits that make them more susceptible to cancer and
dementia. It also represents the first step away from generalised medicine, where people
are treated based on population averages, to precision medicine based on an individual’s
personal biology. Combining genetic engineering with artificial intelligence is likely to lead
to radical improvements in medicine. However, genome editing as a means to deploy
human augmentation bears risks and vulnerabilities since such changes could be targeted
by ‘genetic’ weapons.
Future challenges. Genetic engineering is still at an early stage of development and is
only just moving from the laboratory to human trials. Numerous challenges remain, not
least the need to develop new vehicles to carry the genetic code and better understand
the unintended side effects. The most significant challenges, however, are ethical and
social in nature. These will be covered in Parts 3 and 5 respectively.
12 University of Cambridge, PHG Foundation, ’Somatic genome editing: an overview’.