For about £150 (or more) you can have your DNA analysed, and get a range of comment about what diseases and conditions you might be more susceptible to, compared with the average person.
But what can you usefully do with the information, and is it worth bothering?

The Tests

The most widely publicised tests are from the organisation “23andme”. It’s got that name as the human genome has 23 chromosomes, each made up of sets of DNA.

The standard health test “Health and Ancestry” from 23andme retails for about £150. According to their website, you can “Learn how your genetics can influence your chances of developing certain health conditions.”
For the majority of older people, the relevant tests are about genetic risk for:

• Type 2 Diabetes
• Age-Related Macular Degeneration
• Alpha-1 Antitrypsin Deficiency (lung and liver disease)
• Celiac Disease (gluten-related autoimmune disorder)
• Familial Hypercholesterolemia (very high cholesterol)
• Hereditary Amyloidosis (TTR-Related) (a form of nerve and heart damage)
• Hereditary Hemochromatosis (HFE‑Related) (iron overload)
• Hereditary Thrombophilia (harmful blood clots)
• Late-Onset Alzheimer’s Disease (the APOE gene)
• Parkinson’s Disease

The organisation CircleDNA has a more comprehensive package for about £500, but like 23andme, most results are about ancestry and ‘traits’ (eg. Whether you’re more likely to have a fear of heights), rather than warnings of disease risks.

Is it worth it?

The most well-known test of genes (“BRCA”) is related to breast cancer, thanks to Angelina Jolie, and it certainly looks convincing. However, this test is only applicable to certain ethnic groups, and the National Health Service says that if you don’t have any family history of cancer, it’s unlikely you have one of the faulty genes anyway.

It probably makes more sense for younger people to have such tests, as it gives more time to take steps to reduce risks. Also, a younger person planning to have a family may wish to know if a faulty gene is inheritable. For older people, there’s maybe not a lot you can do anyway in terms of prevention, for example if you learn that there’s a slightly increased risk of some form of cancer.

Possibly the test of greatest interest to an older person is the APOE test for increased risk of Alzheimer’s Disease. Having an adverse result does imply an increased risk, and that might be a call to action to take measures with diet and lifestyle to counteract the extra risk.

There’s some concern that DNA results may pose a risk to identity and security. This partly stems from suspicion that, one day, governments may compel companies like 23andme to make the data available. There’s always of course the potential for hacking and theft of such data.

Before taking a test, you have to consider whether you or your family really want to know about risks, if there’s not much you can do about it. Also, if it reveals an actual condition, then you may have to disclose that, for example when purchasing health or travel insurance.
Right now, under current legislation, there’s no obligation to reveal the added probability/risk of a disease, but of course things could change in the future …

Link to my post on “Alzheimer’s Disease