Heart surgeon shares ‘number 1 gene test’ to determine your risk of dementia and Alzheimer's disease
Dementia and Alzheimer's are often considered problems of old age, but these are highly influenced by genetic markers. Dr London shares the gene that matters.
Dementia and Alzheimer's disease are often viewed as inevitable consequences of ageing, but genetics plays a far more influential role than many realise. Certain gene variants can significantly shape an individual’s risk decades before symptoms appear. Understanding your genetic profile does not predict destiny, but it can offer valuable insight into your risk factors and empower you to make informed lifestyle choices early - potentially delaying or reducing the impact of cognitive decline later in life.
Dr Jeremy London, a board-certified cardiothoracic surgeon with over 25 years of experience, has highlighted the single most important genetic test used to assess an individual’s risk of dementia and Alzheimer’s disease. In an Instagram video shared on December 16, the heart surgeon explains the role of this gene and how its variants influence individual risk factors.
The dementia gene
Dr London highlights that Alzheimer’s disease and related dementias are among the leading causes of death and some of the most devastating diagnoses for patients and their families, noting that the condition also has a strong genetic component. One of the most helpful ways to assess your risk is APOE gene testing.
He explains, “The APOE gene has three common variants - APOE2, APOE 3, and APOE4. You inherit one copy from each parent, so everybody has two. The APOE2 variant is the lowest risk. APOE3, which is the most common, has a neutral risk. And APOE4 is the highest risk, with up to 10 to 15 times higher risk.”
What does this mean?
Dr London explains that the APOE gene plays a key role in brain repair and toxin clearance, with its different variants varying in how efficiently they carry out these functions. He states, “APOE4 is less efficient at both, while APOE2 appears to be neuroprotective.”
The heart surgeon emphasises that identifying genetic risk through testing is neither a definitive diagnosis nor a death sentence, but a tool to understand your risk profile and make informed lifestyle changes early. He highlights, “APOE4 is not a definitive diagnosis of Alzheimer's or a death sentence, just like APOE2 doesn't make you immune, but knowing your risk matters. It allows you to be proactive with lifestyle choices. You can't change your genes, but you can move the needle in your favour.”