Biology | The Mystery Of Innate Genetic Memory: A Bridge Between Biology & Behaviour

Imagine a world where behaviours, fears, or even instinctive skills are passed down through generations – not through observation or storytelling around campfires, but encoded within the biological blueprint of life itself.

Innate genetic memory is that concept. It has been the focus of scientific inquiry for decades, positioned at the intersection of genetics, evolution, and neuroscience. Only very recently has the field begun to bear fruit.

So, What Is Innate Genetic Memory?

Innate genetic memory is the concept that certain predispositions, instincts, or behaviours are inherited biologically, rather than learned socially or through experience. These are not ‘memories’ in the conventional sense of recalling specific events, but rather inherent capabilities or responses designed to aid survival.

For instance, newborn animals display innate behaviours, such as a spider spinning its web or a bird migrating south for the winter – actions that are not learned but are instinctively known. The same applies to humans; reflexes like a baby’s ability to suckle, blink, or the Moro reflex exemplify the innate biological programming present across all species.

But it's not just behaviours and reflexes; it’s also what we fear and how we process that information, which in turn shapes how we think. A study by the Max Planck Institute in 2017 examined the responses to four categories of visual stimuli: flowers, fish, snakes, and spiders. To eliminate any developed or learned biases, the researchers used six-month-old infants and measured their pupil dilation responses. They found a significant difference in stress responses when viewing spiders and snakes, suggesting the existence of an evolved mechanism that prepares humans to acquire specific fears of ancestral threats.

It's likely to be something that exists in all species. Take the infamous YouTube videos of cats being afraid of pickles and cucumbers. Although not definitive, it is thought that this fear response stems from their innate genetic memory, where the long, thin shape is perceived as a threat because it resembles a snake.

If this quality truly is present throughout all species, it suggests that repeated experiences or adaptive responses over evolutionary timescales might be encoded in an organism's genome, serving as a survival toolkit passed from one generation to the next.

Innate Genetic Memory vs. Genetic & Epigenetic Inheritance

While innate genetic memory is often discussed and categorised alongside genetic and epigenetic inheritance, there are critical distinctions, even though there is some overlap in how it functions.

Genetic inheritance refers to the direct transmission of DNA sequences from parents to offspring, determining physical traits such as eye colour, height, and predispositions to diseases. It does not, however, encompass the inheritance of experiences or adaptive responses shaped by an individual’s environment.  

Epigenetic inheritance involves changes in gene expression without altering the underlying DNA sequence. Influenced by environmental factors such as stress or diet, these changes can sometimes be passed on to offspring, affecting their behaviour or physiology. 

Innate genetic memory differs completely from both of these concepts in that it pertains specifically to behaviours, instincts, or predispositions encoded over long evolutionary periods. Unlike genetic inheritance, which involves a fixed biological blueprint, or epigenetic inheritance, which is more adaptable and influenced by the environment, innate genetic memory centres on survival-related instincts deeply embedded in our biology.

4 Key Developments In Innate Genetic Memory Over The Last Few Decades & Their Implications

One of the most notable breakthroughs in the field concerns memory formation in the brain. A study published in 2024 found that neurons undergo cycles of DNA damage and repair due to an inflammatory response triggered by the TLR9 protein. This system is believed to be a crucial mechanism for memory persistence. 

It was hypothesised that errors in the DNA repair cycle might contribute to neurodegenerative diseases such as Alzheimer's. If confirmed, this discovery could pave the way for the development of new and effective treatments to mitigate, and even potentially cure, neurodegenerative diseases and trauma-related disorders.

The results of the study also underscore how the inflammatory response in neurons mirrors the immune response to pathogens, suggesting a novel role for immune-like processes in the brain. In relation to innate genetic memory, the research sheds light on how molecular processes in the brain contribute to long-term memory storage, potentially offering insights into how instincts might become genetically encoded over evolutionary timeframes.

The next development in the field centres on epigenetics. A study conducted back in 2013 demonstrated how stress and trauma can leave marks on DNA that are transmitted to subsequent generations. The researchers conditioned mice to exhibit fear responses to specific scents and found that this behaviour could be inherited by the mice's offspring, thus emphasising a link between behavioural traits and biological memory.

In the realm of immunology, the concept of 'trained immunity' emerged, in which innate immune cells, such as monocytes, exhibit memory-like behaviour through inherited mechanisms. This phenomenon, triggered by vaccines such as the BCG vaccine, reprogrammes immune cells to respond more effectively to unrelated pathogens. 

Part of the reason this discovery is so groundbreaking is that, until now, innate immune system cells like monocytes and macrophages were thought to lack the memory capabilities of their B and T cell counterparts. It is believed that this trained immunity relies on the epigenetic and metabolic reprogramming of innate immune cells.

Finally, a study conducted in 2020 identified neural pathways and genetic markers associated with innate behaviours in animals, using advances in neuroimaging and research into white matter connectivity. It challenged the traditional localisation-based views of brain functions, instead advocating for a network-based perspective on cognitive function. The study aimed to bridge the gap between brain structure and function and to demonstrate how behaviour is shaped by evolutionary forces – an understanding that could transform how psychologists and various other medical fields approach health problems.

Innate Genetic Memory & AI: An Ethical Question

While these developments demonstrate that the gap between biology and behaviour is gradually being bridged, they have also inadvertently revealed their potential to revolutionise another field — artificial intelligence.

Understanding and quantifying the fundamental mechanics of genetic memory may provide the foundation for developing AI systems capable of learning and adapting in ways that mimic biological instincts. In other words, it could serve as a stepping stone to recreating a digitised form of the program we call life. The question is, should it be done?

But even the fact that it could be done may raise uncomfortable ethical and philosophical questions about the origins of free will and identity. After all, if in the future life can be provably demonstrated to be merely a collection of innate and environmental algorithms beyond our control, are we a living machine or simply a machine that believes it’s alive?

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