Cut + Paste online exhibition

• Your genome is made up of DNA - long chains of chemicals arranged in a sequence that are tightly coiled into a spiral called a double helix. Sections of these chemical sequences are called genes, and they control different elements of your body’s growth and development, and how your body functions.
   
• Half of your DNA comes from your mother and half from your father - this is why you inherit similarities in the way you look, but also why some diseases or conditions can be passed on from one generation to the next. 
   
• Your body is constantly copying its genome as it grows and replaces cells. Very occasionally, errors occur during the copying process which can lead to diseases such as cancer. 
   
• Each strand of coiled DNA is called a chromosome. Most humans have 46 chromosomes arranged in 23 pairs. Almost every cell type in the body has a full set of these chromosome pairs in its nucleus, the cell’s ‘control centre’. 

• Your genome can influence many things about you from the colour of your hair and the shape of your toes to how likely you are to develop certain diseases. But is there more to you than your DNA? 
   
• There are lots of other factors that can influence how you develop, from the food you eat (or your mother ate while you were in the womb) to how much you exercise; whether you drink or smoke; and the climate that you live in. 
   
• We all ‘enhance’ ourselves to some degree: whether it is through education, using drugs such as caffeine to increase alertness, wearing make-up, working out, or even undergoing surgery to change the body. 

• Humans have been shaping the genomes of plants and animals for centuries by carefully selecting and breeding certain species that have desirable traits. This has been carried out with animals such as dogs, cattle or sheep, and with plants such as tomatoes, wheat or corn. Genome editing tools allow scientists to introduce faster changes with a wider range of possibilities.
   
• One of these genome editing tools is called CRISPR (pronounced “crisper”). CRISPR can be programmed to recognize and ‘cut’ a snippet of DNA and ‘paste’ in a new piece. The edit can be made on a very tiny or a much larger section of DNA. This editing process is very useful for scientists trying to work out what certain genes or sections of DNA do. Their discoveries can help in the treatment of diseases such as cystic fibrosis and some cancers, as well as the development of new ways to fight malaria by editing mosquito genomes. 
   
• Today, around 80% of labs at the Crick use new cutting and pasting tools to target and edit specific parts of the genomes of different organisms - including animals, fungi and bacteria. One example used by some labs at the Crick involves genome editing zebrafish. As young zebrafish are transparent, their major organs are very visible, which makes it a really useful model organism for understanding cell development. To identify and highlight specific organs and cell types, genome editing is used to insert light-emitting genes from other organisms, such as jellyfish, into the zebrafish embryo. This means researchers can ‘tag’ particular cells so they emit different coloured light, and they can analyse them more easily and in real time.
   
• A person’s genome can be edited to treat a specific disease - this is called a ‘somatic’ edit. For example, somatic editing is being trialled to treat people with sickle cell disease. The treatment will not change the genome of any future children they may have. Changes to the genome that can be passed on are carried out on egg and sperm cells or very early embryos, and they are called ‘heritable’ edits. Heritable genome editing is not currently legal in the UK.  
   
• Genome editing tools are advancing all the time and in the future they could allow us to edit the genomes of plants, animals and humans more quickly, easily and accurately than ever before.  

Currently, somatic genome editing treatments (which only affect the body of the person being treated, and not future generations) are being trialled for a number of conditions that are caused by variants in specific single genes. These include blood diseases like sickle cell disease and haemophilia B, some inherited forms of sight loss, leukaemia and several other cancers. 

It is not yet possible to use genome editing as a treatment or cure for conditions that can be caused by the combined effect of multiple gene variants, such as heart disease and diabetes.

Currently it is not legal in the UK to use heritable genome editing (where the edit would affect all future generations) to alter an early embryo, eggs or sperm to prevent passing on a particular genetic condition. If a person wishes to avoid passing on a particular genetic condition, they may use genetic testing. One type is prenatal testing, which is carried out on a pregnant person or the embryo they are carrying.

Another type is pre-implantation genetic testing, which can only be used to test for conditions where one specific gene is the known cause. To use this, prospective parents create a number of embryos using in-vitro fertilisation (IVF). Pre-implantation genetic testing then allows the selection of embryos that do not carry the specific gene variant that causes the inherited condition.  Those embryos are then transferred to the parent’s womb.

Could genome editing be used to ‘enhance’ the human body, by editing in traits that are considered ‘desirable’? Even if it were legal (which it isn’t in the UK and many other countries), heritable genome editing is not currently capable of allowing people to ‘design’ babies, and it isn’t likely to be in the near future. Many human traits are shaped by a complex combination of factors, which may include several or dozens of genes, as well as the impacts of nutrition, environment, lifestyle and life experiences