![\"A](\"https:\/\/blogs.otago.ac.nz\/thesheet\/files\/2025\/10\/part-of-the-fibroblast-growth-factor-receptor-3-protein-685168.png\")
<\/a>Genetic testing<\/h2>\n\n\n\n
Genetic testing identifies changes in chromosomes, genes, or proteins. The results can help determine whether a person has a suspected genetic condition or might develop a genetic condition. The results can also inform a person’s chance of passing on a genetic disorder.<\/p>\n\n\n\n
Genetic testing has limitations: some tests can’t detect all of the possible mutations that can cause a condition, or the mutations that can be identified may only lead to a condition only some of the time.<\/p>\n\n\n\n
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- If screening for Batten disease was available, what implications would there be for potential patients and their parents?<\/li>\n<\/ul>\n\n\n\n
Imagine if you find out you have a mutation, one that might give you a disease in the future, and you could pass on to your children.<\/p>\n\n\n\n
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- What happens when you are looking for someone to marry, or when you want to get health insurance, or when you are deciding on a career?<\/li>\n\n\n\n
- Would you want to find out about that mutation if there was no treatment for the disease?<\/li>\n<\/ul>\n\n\n\n
The National Institute of Health in the USA provides an overview of different genetic tests:<\/p>\n\n\n\n
Genetic Testing – Medline Plus<\/a><\/p>\n\n\n\n
![\"A](\"https:\/\/blogs.otago.ac.nz\/thesheet\/files\/2025\/10\/gel-in-which-dna-has-been-separated-using-electrophoresis-685167.jpg\")
<\/a>
A DNA electrophoresis gel, which scientists use to separate pieces of DNA of different sizes. Some genetic tests use DNA electrophoresis to reveal gene mutations.<\/small><\/figcaption><\/figure>\n\n\n\nGermline vs somatic gene therapy<\/h2>\n\n\n\n
Somatic<\/strong> gene therapy is DNA treatment targeted at cells in a person’s body that are not passed on to the person’s children, ie somatic cells. The treatment that Dr. Hughes is developing for children with Batten disease is an example of somatic gene therapy.<\/p>\n\n\n\n
Germline<\/strong> gene therapy is DNA treatment targeted at a person’s cells that produce reproductive cells, eggs or sperm. The treatment is then passed on to that person’s children and grandchildren.<\/p>\n\n\n\n
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- What would be the advantages of germline therapy?<\/li>\n\n\n\n
- What problems can you think of that might make germline therapy unacceptable?<\/li>\n\n\n\n
- Do you think germline therapy should be used in humans?<\/li>\n<\/ul>\n\n\n\n
An editorial in the Nature<\/em> journal talks about the ethics around germline editing used in human embryos. It refers to a recent example of genetic editing of human embryos where scientists used the technique to find out about how a gene works (the embryos were not allowed to develop into babies):<\/p>\n\n\n\n
Take stock of research ethics in human genome editing – Nature<\/em><\/a>, 2017<\/a><\/p>\n\n\n\n
Taking away the choice of offspring to decide<\/h2>\n\n\n\n
There is now a new tool available that can very accurately edit the DNA in a cell without using viruses. It is called CRISPR-Cas9, and has been adopted from bacteria. In theory, it could be used to fix mutations in an embryo.<\/p>\n\n\n\n
![\"A](\"https:\/\/blogs.otago.ac.nz\/thesheet\/files\/2025\/10\/photo-of-issie-robertson-680842.png\")
<\/a><\/figure>\n\n\n\nIssie Robertson, a teenager from Dunedin, wondered if modifying a human embryo to extend its life could be considered ethical. The sixteen-year-old even wrote an essay about these concerns that was published in the Journal of Medical Ethics.<\/p>\n\n\n\n
Listen to Issie talk about her concerns on Radio New Zealand National:<\/p>\n\n\n\n
Issie Robertson – Teen takes on bioethics – RNZ, 2017<\/a><\/p>\n\n\n\n
You can read the abstract of her essay:<\/p>\n\n\n\n