Genetic Reservoirs: An Exploration of Proto-Quirk Sequences in Pre-Quirk Genetics and Phenotypic Quirklessness in Modern Populations

The Turning Point of Humanity

Common knowledge states that the first emergence of a Metahuman Ability was the famous Luminescent Baby of Keikei, China. The birth of this child serves as a distinct turning point in the history of humanity- a single second that sharply divides the pre-metahuman era from the metahuman era. Common knowledge also states that up until the emergence of the first Metahuman Abilities and Traits, what are now called Quirks, all of humanity for all of its history had been Quirkless. For the colloquial meaning of the term, where Quirkless merely serves as an indicator that an individual does not outwardly manifest an ability or heteromorphic trait, this is undeniably true.

On a genetic level, though, the story is very different on both accounts.

While the science of quirk genetics is still in its infancy, the source of quirks has been narrowed down to a specific section of the genome- specifically, the 7th chromosome. When comparing genetic sequences of ancestral humans, the 7th chromosome of individuals with quirks has a section of additional DNA on the short arm of the chromosome, now called the ‘quirk sequence’. The origin of this DNA is still highly debated with everything from viral infections to solar flares suggested as the cause, but whatever its source, it is undeniably the primary location of quirk genes. If common knowledge as described above were to hold true, then the Luminescent Baby should have the oldest known quirk sequence, and modern ‘Quirkless’ people should be missing this section of DNA, but neither is the case.

The Chinese Woman and other Pre-Quirk Quirk Sequences

The earliest evidence of quirk sequence formation comes from a grave in Northeast China dating back to the early 17th century. This individual, an unknown female approximately in her late 30s, shows a lengthening in the 7th chromosome above the centromere in what is being called a proto-quirk sequence. This proto-quirk sequence is approximately a third as long as modern quirk sequences, which lead many to initially discredit the claim as an unrelated mutation. Further testing has since revealed that almost all of the specific genes in this woman’s proto-quirk sequence are found in modern quirk sequences in some variation, and one has been found to be highly similar to a particular gene associated with quirks that involve temperature resistance.

Similar proto-quirk sequences have been identified in other individuals predating the birth of the Luminescent Baby. The majority of these cases have been identified in the century preceding their birth, but this is most likely a selection bias because many are being found through re-examination of the data from the short-lived ‘ancestry test’ phenomenon of the early 21st century. It is also possible that there are older examples of the proto-quirk sequence that simply haven’t been found or identified yet.

Modern Quirklessness

Conversely, if one were to sequence the genome of most modern ‘Quirkless’ people, they would most likely find a fully present, fully developed quirk sequence. In 2XXX, the Institute for Metahuman Research in Sierra Leone [IMR] completed genetic sequencing from a pool of Quirkless volunteers from nearly every country and found that of the 4958 genomes sequenced, only 238 had significant anomalies in their quirk sequences, which were divided into 3 categories.

The first category contains 86 individuals with shortened or diminished quirk sequences that more closely resemble the proto-quirk sequences found in the aforementioned Chinese Woman and 21st century ancestry tests. The second category contains 55 individuals with mutations in or around the quirk sequence that prevented it from being expressed. Essentially, these are people who have the genetic capacity to have a quirk, but an outside mutation prevented it from actually manifesting. The third category contains 97 individuals who had entirely absent quirk sequences. The remaining 4720 individuals in the study had completely normal quirk sequences.

The question, then, is why. Why was the Chinese Woman not the first known emergence of a Metahuman Ability? Why do so many people with developed quirk sequences never go on to manifest their abilities? Why are so few phenotypically quirkless people truly quirkless on a genetic level? The answer comes down not to the presence or absence of the quirk sequence but instead to the specific genes contained within it.

The Genetic Basis

Common knowledge states that most individuals inherit their quirk from their parents- either by directly copying one of their parents’ quirks, copying one with minor changes, or combining the two of them in some way- or, rarely, by mutating an entirely new quirk. Unlike the previous two pieces of common knowledge, this one is at least partially correct. Quirk inheritance is not a simple mendelian inheritance but is instead a complicated interplay between multiple gene types within the quirk sequence. As with much of the human genome, the quirk sequence contains large segments of non-coding DNA, but among those segments, the average quirk sequence contains 25 to 40 quirk genes interspersed with 60-100 pairs of regulating sequences. Together, these genes control a person’s quirk.

Regulating Sequences

The variation found within regulating sequences is staggering- the Quirkless study done by the IMR identified more than 3,000 variations on regulating sequences within their 4958 participants alone, and other studies have found similar levels of diversity within their subject pool. Even with this immense amount of variation, there are patterns that have emerged.

Barring mutations, regulating sequences come in pairs that typically flank a quirk gene. One half controls the type of expression of the associated quirk gene, and the other half controls the strength. 75 to 85% of the variation found within regulating sequences are found in the half that codes for strength of expression, though the exact percentage varies from study to study. Because of this, strength controlling sequences are less well-documented than their expression controlling counterparts and often harder to classify.

Strength Controllers

The strength controlling half of the regulating sequence is, as the name implies, responsible for the amount of expression of the paired quirk gene. The most common method of classification ranks these sequences on a scale of 0 to 9 with 0 being so weak as to be barely noticeable and 9 being exceptionally strong. It is not uncommon for a range to be given instead of a specific number due to the difficulty in determining exact numbers.

The most common number range for strength controllers is from 3 to 5, though among those in the heroics profession, those numbers skew higher, into the 4 to 7 range. It is thought that strength controllers can become stronger within a single user through events where the user is under extreme stress, often called ‘quirk evolutions’. During these events, it is not uncommon for multiple mutations to occur in a user’s quirk sequence in multiple locations.

Other classifications systems such as the Dutch System, which is popular in some European quirk and genetic institutes, instead sorts them into Weak, Average, and Strong expressors. One criticism of the Dutch system is that it does not account for the 0 strength score, which functionally serves to disable the associated quirk aspect. While it is technically possible for a quirk gene paired with a 0 strength controller to manifest some aspect of itself, it can only really be done via modifying or ‘piggy-backing’ onto the expression of another quirk gene. The Dutch-Cuban system answers this by adding a ‘Minimal expressor’ category, but some feel that it is not a complete enough classification system. At this time, no universal classification standard has been put forward.

Expression Controllers

Unlike the strength controllers, there is near-universal consensus on the categorization of expression controllers. The expression controlling half of the regulating sequence is classified as one of three categories. The first are ‘suppressors’, which prevent or minimize the expression of the quirk gene. The second are ‘primary expressors’, which increase the genetic dominance of the quirk gene, often leading to it becoming a main feature of the user’s quirk. The third are ‘secondary expressors’, which allow the expression of the associated quirk gene, but in a manner that is recessive to any paired with a primary expressor, meaning it will still be present but in a diminished or subservient way.

One feature of the strength controller that has been noticed across many studies from many different institutes is that primary expressors have the highest rates of variation. While the average individual only has 0 to 5 primary expressor sequences, or 0 to 8%, they account for 25% of all identified expression controllers. Most individuals have 50 to 60% secondary expressor sequences, and they account for 50% of all identified expression controllers. Suppressors account for the remaining 32 to 50% of the expression controllers in any given individual, but they have the lowest rate of genetic diversity with only 25% of identified sequences falling into this category.

The prevalence of expression controllers, like those for strength controllers, is a bit different among those in the heroics profession, but not to the same extent. The average hero has 3 to 6 primary expressor sequences, but the relative proportion of secondary expressors and suppressors remains the same. Unlike strength controllers, expression controllers do not often mutate during so-called ‘quirk evolutions’.

Loose Pairs

While regulating sequences primarily affect a quirk gene that is between any given pair, it is not uncommon for there to be ‘loose’ pairs of regulating sequences that do not have an associated quirk gene. Research on the effects of these regulating pairs without an associated quirk gene is still underway at this time. Current leading hypotheses suggest these may enhance or alter the effects of nearby regulating sequences and serve as buffers during genetic recombination events, but this has yet to be demonstrated in replicated studies.

It is also theorized that 'loose pairs' play a role in propagating advantageous mutations that occur in one cell through the other cells, but as with many other aspects of quirk propagation, this is not fully understood. In fact, that particular aspect of quirk genetics is arguably the most mysterious, though not for lack of trying.

Quirk Genes

Quirk genes, as the name implies, are the segments of the quirk sequence that actually contain information on what the quirk will do. The variation found within quirk genes is similar to the level of variation found within regulating sequences. Studies done at genetic and quirk studies institutes across the world have, in aggregate, identified over four million different quirk genes, many of which have what have been described as ‘child genes’, or genes that have minor point mutations from the ‘original’ gene within descendants of the ‘original’ gene holder.

Quirk genes are difficult to classify at this time due to several factors. The large number of quirk genes within the population means that simply locating each of them would require genetic testing on a scale far greater than any institute currently has the resources for. The high rate of quirk gene mutation also contributes to this by increasing the number of quirk genes in existence with every generation. These genes are also known to mutate during ‘quirk evolutions’.

The greatest obstacle to classification of quirk genes, however, is the complexity of gene interaction within the quirk sequence. Since the average quirk sequence contains 25 to 40 quirk genes, it can be difficult to pinpoint which sequence is responsible for which aspect of the user’s quirk. Some more common aspects, such as the temperature resistance code in the Chinese woman’s proto-quirk sequence, have been identified through isolating specific nucleotide sequences that correlate with particular functions, but many aspects of quirks are unique or rare enough to make this impractical to impossible.

The Chinese National Human Genome Center, Beijing [CHGB] is reportedly working on a classification system using artificial intelligence to help identify potential effects of various quirk genes, but this project is still in its early stages and is not yet available to the international quirk studies community.

Stabilizer Sequences

There is only one type of quirk gene that is immediately classifiable- exceptionally short quirk genes that do not appear to code for any particular quirk aspects. The presence of a large number of these genes in an individual’s quirk sequence often correlates with a ‘weak’ or entirely absent quirk, so early research often mis-classified these sequences as an entirely separate type of gene. Originally, they were called ‘non-coding interrupter’ sequences [NCI] as it was believed that they were either damaged quirk genes or segments of non-coding DNA that were placed incorrectly during genetic recombination and disrupted the formation of quirks.

The University of Auckland Bioengineering Institute [UABI] proved that assumption wrong in 2XXX with the publication of their research that showed these NCI sequences were actually serving to stabilize both the quirk sequence as a whole and the manifestation of quirks. It is true that individuals with high numbers of these newly-renamed ‘stabilizer sequences’ often have less readily apparent or more limited quirks, but the inverse is also true.

Individuals who have very few stabilizer sequences often have very powerful quirks that are very dangerous to the user. This is referred to as a Quirk Gene Overload. This can also be the case if someone holds a particularly strong or dangerous quirk gene - a ‘Powerhouse’, as some have called them- that is paired with a high strength controller and a primary expressor. In cases such as those, the user typically requires more stabilizer sequences to avoid a dangerously powerful quirk.

The number of stabilizer sequences in any individual varies greatly. 30 to 70% of an average individual’s quirk genes are stabilizer sequences, with the median falling around 60% for the general population. Among Heroes, however, the range pulls down to 20 to 50% with the median around 38%.

Some argue that these stabilizer sequences are not actually quirk genes but are, in fact, a separate type of gene as originally identified. There is no current consensus on this proposition, but a simple majority of current literature on the topic considers them to be a subtype of quirk gene.

Further research from UABI has shown that these stabilizer sequences are highly adaptive and show high rates of mutation, often in response to increased quirk use. The exact mechanism is not known, but these stabilizer sequences seem to be adapting to protect the user from their own quirk as quirks become more powerful. Some hypotheses currently under investigation suggest that they may also be partially responsible for the phenomenon of ‘quirk evolution’. It has been suggested that, in response to high levels of stress, one or more of these stabilizer sequences may deactivate or mutate into weak quirk genes, allowing the user’s quirk to strengthen while potentially making it more dangerous.

Additional research from the CHGB has found a correlation between fetuses with a low percentage of stabilizer sequences and higher rates of miscarriage. The only known case of an individual with no stabilizer sequences was a stillbirth in eastern Russia in 2XXX. It is likely that other cases where there were no stabilizer sequences present have occurred but resulted in miscarriage, stillbirth, or early death.

Stabilizer sequences have also been found to affect the expression of genes outside of the quirk sequence. The most common visible effects of this expression cause the development of three phalanges and two joints in the smallest toe. The fusion of the first and second phalanges of the smallest toe has long been paired with the development of quirks, but as with other pieces of common knowledge, this is not quite correct.

The fusion of the phalanges was already quite common long before the advent of quirks. Data from 1995 shows that approximately 75% of the Japanese population and approximately 40% of the European population already lacked a second joint in the smallest toe. The truth is not that quirks correlate with fusion of the joint but rather that a high number of stabilizer sequences often causes those phalanges to un-fuse in individuals that would otherwise have fused phalanges. Further research is currently underway to determine other gene expressions that the stabilizer sequences might affect.

The Meaning of Quirkless

The question is, then, what do these various types of genes in the quirk sequence have to do with proto-quirk sequences and the modern quirkless population. The answer lies with the regulating sequences and stabilizer sequences discussed above.

The Chinese Woman and other Pre-Quirk Quirk Sequences

The Chinese Woman’s proto-quirk sequence contained only one ‘true’ quirk gene- the one associated with modern temperature resistance genes. The other 12 present in her genome were stabilizer sequences. Additionally, she had only 1 primary expressor, 2 secondary expressors, and 24 Suppressors. Not all of the strength controller sequences could be identified, but of the 7 sequences with estimated ratings, none were higher than a 2. The primary expressor sequence, which would theoretically have made her abilities quite noticeable, was paired with a stabilizer sequence, meaning it had no effect. The temperature resistance quirk gene was paired with an unidentified strength controller and a secondary expressor, so if the gene was expressed at all, it likely would have been in a relatively minor way.

Perhaps the Chinese Woman would have been comfortable in lower or higher temperatures than her peers, or perhaps she could have handled hotter objects before burning herself, but it most likely would have been in ways that would not stand out as unusual. A similar pattern of low strength scores, high instances of stabilizer sequences, and ‘loose’ or stabilizer-paired primary expressors has appeared in other proto-quirk sequences identified in other pre-quirk genomes.

It is also possible that incredibly gifted individuals from history may have actually had the first manifestations of quirks, though in much more subtle ways than the Luminescent Baby. If these quirks were not fantastical- such as intelligence or strength-boosting quirks- there would have been no way for pre-quirk people to know that it was not just an exceptionally talented or exceptionally powerful person.

Modern Quirklessness

The other side of that coin is that, as previously discussed, most modern ‘quirkless’ people actually have complete quirk sequences and are not actually genetically quirkless. The phenotypic quirklessness can arise through several different pathways.

The first genetic basis of phenotypic quirklessness is for an individual to actually be genetically quirkless, or “True Quirklessness”. These would be cases where the quirk sequence is entirely absent from the genome. In the modern day, this is incredibly rare, with studies such as the IMR study from 2XXX indicating that only about 1% of phenotypically quirkless people have True Quirklessness, or .02% of the total population.

The second genetic basis of phenotypic quirklessness, as discussed from the IMR study, is for some mutation in or around the quirk sequence to disrupt its ability to express a quirk that is otherwise coded for. Individuals with this type of quirklessness are often the result of prenatal exposure to radiation or certain toxins that affect the development of the fetus. These are commonly called cases of “Suppression Quirklessness”. These are also often the source of so-called ‘late bloomers’ as a spontaneous mutation can counteract or bypass the mutation that originally prevented the manifestation of the quirk.

The third genetic basis of phenotypic quirklessness is for there to be some combination of regulating and quirk genes that prevents the expression of a quirk. If an individual had all of their quirk genes paired with either a very low level strength controller or a suppressor and all of their Primary and Secondary expressors paired with stabilizer sequences, then there would be no expression of a quirk despite the pieces for one being present in the genome. This is commonly called “Gene-Match Quirklessness”.

The fourth genetic basis of phenotypic quirklessness is for an individual to have a quirk sequence that inherently codes for no quirk through only having stabilizer sequences. These individuals may have any combination of regulating sequences, but there are no quirk genes for them to express. This is commonly called “Coded Quirklessness”.

Genetic Reservoirs

Common knowledge states that quirklessness is dying out and will one day be a thing of the past, and that the current quirkless population is just a useless legacy of a previous state of evolution. After all, in just over 200 years we have gone from maybe 500 people on Earth with quirks to just over 80% of the population with quirks. It would make sense for that trend to continue. Quirks seemingly give the user a distinct advantage over quirkless people, especially when considering that the social stigma of quirklessness is on the rise in most countries, mirroring the stigma that quirks held just two centuries ago.

It is true that as time goes on, True Quirklessness is becoming more and more rare as the remaining proto-quirk sequences mutate into full quirk sequences and through reproduction. It is also true that True Quirklessness fully predated the advent of quirks. This, however, does not mean that quirklessness is merely a throwback, or that quirklessness is dying out.

In the early days of quirk development, when the genes that would later become quirk sequences were first beginning to exist, the forms of pseudo-quirklessness found in the Chinese Woman and others like her allowed quirk genes to develop in ways that maintained the user’s safety. These shorter proto-quirk sequences are almost entirely filled with stabilizer sequences, weak strength controllers, and suppressor and secondary expressors. While this combination of genes prevented these historic figures from manifesting what we would call quirks, these tempered genes allowed the quirk sequence to expand and grow to its modern size without endangering the lives of their holders due to quirk gene overload.

Even to this day, the most common forms of modern quirklessness- Gene-Match and Coded Quirklessness- are, in fact, integral parts of maintaining quirks within the population. As mentioned previously, stabilizer sequences are a crucial part of maintaining the balance of powerful quirks because individuals with low stabilizer sequence percentages or a few Powerhouse quirk genes are at a much higher risk of being inherently harmed by their own quirk. Under the pressures of simple natural selection, those with these types of quirks would simply not be able to reproduce as frequently, which would maintain the balance of coding-genes-to-stabilizer-sequences in the population overall.

The issue comes in when we consider the rapid rates of mutation in both quirk genes and stabilizer sequences. In ‘quirk evolutions’, multiple different types of genes have been known to mutate into stronger versions. Strength controllers can allow a more potent expression of an aspect of a quirk. Quirk genes can mutate into altered, often more powerful versions of what they were. Stabilizer sequences can mutate to the point of deactivation or, in rare cases, mutate into weak quirk genes that are then subject to the same mutation potential as other quirk genes. In addition, these same mutations can occur across generations, leading to more powerful and more intricate quirks with each passing generation.

Overall, this leads to a higher prevalence of Powerhouse quirk genes at the same time as it removes stabilizers from the population. If this were allowed to continue unchecked, then eventually quirks so powerful that they would harm their user would not only be the norm, but they would be the only option due to the lack of stabilizer sequences available to counteract the powerhouses or take spaces to prevent quirk gene overload.

This is where the quirkless population comes in. Since they have no quirk, their quirk sequences are not subject to the stress mutations that come along with frequent use and ‘quirk evolutions’. They serve as a form of genetic reservoir to store inactive versions of less powerful quirk genes. When, not if, quirks become too powerful, these safeguarded genes serve as a release valve to temper quirks and maintain balance within the overall population.

Even as quirks become more powerful, quirkless people will continue to be born through mutations and random chance, not because the people who end up quirkless have bad luck, but because they are a vital part of natural quirk balancing and have been from the very start. Quirklessness allowed quirks to come into existence, quirklessness allows quirks to exist as they do today, and quirklessness will ensure that humanity does not rip itself apart under the strength of its quirks.