A great part of living in the 21st century is that if you have a device that connects to the internet, you have access to hundreds, if not thousands of experts who are often eager to share in-depth knowledge about the world we live in. 

Someone asked “What is a genetics fact that not a lot of people know?” and people detailed their best facts. From the peculiarities of our DNA to interesting new species of plants, get ready to expand your mind as you read through. Be sure to upvote your favorites and comment your thoughts and ideas below. 

#1

Since navel oranges have no seeds, they are all clones of the original mutated fruit discovered by a Brazilian monk a century ago. The billions and billions of navel oranges that have been grown, sold and consumed since are all genetically identical.

Image credits: JK_NC

#2

Twins can have different fathers.

Image credits: Coded-influx

#3

Most of your DNA is just noise that never gets used, and a significant chunk of it contains echoes of ancient and prehistoric viruses that infected your ancestors.

Image credits: Common_Sense_Dudd

While it might sound like a cross between dystopian fiction and body horror, some researchers believe that there is a lot of potential to store data and information in our DNA. After all, in one sense, that’s exactly what DNA’s actual function is. That being said, most of us probably don’t want to walk around with our own DNA turned into a sort of USB flash stick when we can literally buy this device in most stores.

Comically, as sci-fi as this idea sounds, it might already be out of date. Research into this topic has found that encoding data into our DNA is not only more costly but less reliable and slower to read than the various means of data storage we already have. So if you really want to get cyberpunk, perhaps get a QR code tattooed or investigate the wonderful world of chipping your palms. 

#4

There’s a genetic disease called Laron Syndrome that makes you shorter in stature, a longer life expectancy, and near immunity to cancer and diabetes.

Image credits: Friendly-Reach6443

#5

Your hair shape changes with hormones

Image credits: The-Proud-Snail

#6

40-50% of our DNA is the same as cabbage.

Image credits: Moon_Jewel90

#7

Potatoes have more chromosomes than humans.

Image credits: AccurateEnvironment4

#8

It’s really unfortunate that there are so many people out there that think that it’s the mother’s fault for not bearing sons. No Gregg, she isn’t broken. You’re just blasting X’s instead of Y’s.

Image credits: Hexis40

#9

Pregnancy can alter your DNA as you create a new life. Allergies can appear or disappear, hair texture/colour can change.

Image credits: imgunnamaketoast

#10

There’s this thing called ACHOO Syndrome where it’s estimated that 18-35% of people on Earth have a reflex that induces sneezing due to bright light.

Image credits: HeyImGilly

#11

Cheetahs are extremely inbred. They had a massive bottleneck about 10,000 years ago and had too little diversity to fully recover.

Image credits: confusedbox03

#12

If you set aside ethics and set out to do it, it would only take 33 generations to create a human being who was the descendant of everyone currently alive and able to have children.

Also, pedigree collapse: no living person has as many unique ancestors as they mathematically should. Every person has, biologically, 2 parents, 4 grandparents, 8 great-grandparents, etc, doubling every generation. 30 generations back without any degree of inbreeding would require over a billion unique 28x great grandparents, more than the entire world population for 1100 AD. Every single human’s family tree is full of people marrying and having children with cousins of some genetically-unimportant degree over the last thousand years.

Image credits: Triton1017

#13

The ability to flex the tongue as a cloverleaf is genetic.

Image credits: Irahapeti

#14

There is a gene called TP53 – it’s referred to as the ‘guardian of the genome’ – it is a tumor suppressor gene and prevents cancer of all types. Humans have two copies and if one is broken/mutated it causes an inherited condition called Li Fraumeni. People with this have a very very high risks for cancer, and the condition can be passed down in families. Elephants have 20 copies of TP53 and therefore rarely get cancer. The Li Fraumeni foundation uses the elephant as its mascot and hopefully we can someday figure out how to replace faulty TP53 genes for these families.

Image credits: OrangeMonarchQueen

#15

Twins can be half identical. Like same egg split but two different sperms so they share about 75% genetic similarities compared to 100% in identical twins and 50% in fraternal twins/siblings.
They can even be boy and girl twins.

Image credits: SunRemiRoman

#16

Gastrointestinal issues can be passed on by parents. They run in your jeans

Image credits: Joellama69

#17

UV gives you cancer because literally makes your DNA stick so tightly the only way to fix it is remove the entire section then “guess” what was there. More this happens, more chance cell becomes cancerous.

Bacteria don’t have this polymerase repair so it’s why UV kills them or mutates them.

Plant one – Hexaploid wheat possesses 42 chromosomes derived from its three ancestral genomes. The 21 pairs of chromosomes can be further divided into seven groups of six chromosomes (one chromosome pair being derived from each of the three ancestral genomes)… This is mainly because of how much humans have bred it it’s literally inbred.

Image credits: arabidopsis

#18

All people with blue eyes are descended from the same person

Image credits: Limp-Letterhead1687

#19

Since our mitochondria used to be separate single celled organisms, they have their own DNA

Image credits: Cinnabun6

#20

Hippos are the closest living relative to whales.

Image credits: addilou_who

#21

Not sure what gene but Redheads can take more pain then others also require more anesthesia.

Image credits: tdiz10

#22

Genetic chimera is arguably the most interesting condition. It is possible (and documented) for a woman to give natural birth but the baby not match her DNA test.

Essentially, 2 fertilized eggs merge at a very early stage and developing into a single organism. Different parts of the body comprised of obe or the other genome.

It’s most commonly discovered in domestic animals that have unexplainable color combinations, often (but not always) divided symmetrically.

Image credits: Eagle_1776

#23

Your susceptibility to dental cavities. Dental hygiene matters, but genetics plays a huge role, too.

Image credits: dazzlingestdazzler

#24

Birthing identical twins is not an inherited trait. It’s random. Fraternal twinning is inherited, but only from mother to daughter. My MIL ‘took credit’ for me having identical twins because she had fraternal twin siblings. When I explained that genetics proved her wrong she was not having it!! ?

Image credits: JellyfishEastern8184

#25

If you see a cat with three colors (black, white, and orange), it’s got two x chromosomes.

Cat people tend to know this, but idk about people in general.

Image credits: dancingpianofairy

#26

Some genetic diseases persist because having one copy of the disease causing version of that gene can have benefits, so even though having two copies is deadly, that copy of the gene doesn’t go away in the population. 

Image credits: uxoriousHouseHusband

#27

Perhaps my favourite biology fact is about pharmacogenetics, how your genetics determines the efficacy of drugs on your system due to prevalence of receptors of different types that the drugs target to produce an effect:

“90% of drugs only work on 30-50% of the population.”

I find it so truly wild. But most people I’ve talked to about it seem to agree that some drug or other doesn’t work for them. This really highlights how much of a process finding the right drug for a person is.
I had a lecture on this in uni in about 2016 and it said the future of pharmacology is individual genetic screens for drug effectiveness meaning people don’t have to keep trying different drugs until they find the one that works, you would be tested then your doctor would have that info.
I just hope it overcomes the pushback from Big Pharma in my lifetime cause it would be a true game-changer.

#28

People with moles live longer. Something to do with telomeres.

Image credits: Starkville

#29

One in 5 people can smoke as much as they want and never get lung cancer.

Image credits: Loggerdon

#30

Super rare, but there’s a condition called superfetation where twins in the womb have different gestation dates. Basically, the woman got pregnant, then a few weeks later she got pregnant again.

Image credits: AllOutOfFucks_sorry

#31

Humans are closer genetically to bonobos than chimpanzees.

I wish I was a bonobo.

#32

I’m a geneticist with a mediocre master’s degree in biology and currently pursuing a PhD in Bioinformatics. Here are some insights:

1. The accuracy of consumer and clinical genetic tests is often questionable due to the rapid pace of scientific advancements outpacing their application in the industry. The notable exceptions are information about Neanderthal ancestry (which is significant enough to have earned a Nobel Prize in Medicine) and a few critical mutations like the sickle cell variant and others related to blood.

2. Genetically, most humans are nearly identical, with differences being incredibly minute. This means that, barring age and sex, achieving success in various fields – whether it’s social, intelligence, or physical appearance – is possible without genetic modifications.
Everyone likely has a unique genetic trait that gives them a significant advantage, however. This is currently identifiable only in a lab setting. Understanding your unique trait, which often involves the expression of certain molecules, might require professional scientific interpretation.

3. Many severe genetic diseases, such as insulin-dependent diabetes, are only about 50% determined by genetics. Factors like early developmental conditions, including a mother’s diet during early pregnancy and infections, play a paramount role.

4. Despite common belief, Neanderthals were not a separate species but rather a part of the human family. For perspective, Europeans and the Khoisan people of South Africa have been genetically divergent for about 300,000 years, not much less than the 500,000-year divergence between humans and Neanderthals.

5. Factors beyond genetics, such as living in a highly controlled environment (like a prison), having access to specific nutrition, owning a car and a separate house, and engaging in mental activities like language learning, math, statistics, and team video games, can significantly impact personal development. Genetics helps us understand and appreciate the influence of these non-genetic factors.
The field of genetics is incredibly dynamic and continually evolving, offering many more fascinating insights.

#33

The first crispr-cas treatment for sickle cell has just been approved by the FDA

Image credits: Specialist-Ad432

#34

The genes that determine the size of your male parts are on the X-chromosome, so you inherited that from your mom.

Image credits: Mortlach78

#35

Your immune system regulation genes (HLA) have a huge impact on how you smell!

Image credits: yellowdaisy765

#36

Having five fingers in each hand is a recessive gene. Polydactyly (having 6 fingers on each hand) is a dominant gene.

Image credits: SquirtleBob164

#37

Depression can be genetic.

#38

Two brown eyed parents can have a blue eyed child.

Image credits: catsumoto

#39

That if you unraveled all of the DNA in your body, and stretched it out in a straight line, you’d be dead.

#40

There are more combinations than just XX and XY.

And some of the variations have no outward signs, so you could have one of them and have no idea without genetic testing.

#41

When you’re pregnant, bits of DNA from your baby invade your body and settle all over permanently – including in your brain. Researches found this by looking for male DNA in the brains of deceased 70 year olds. Interestingly, mouse studies have also shown that fetal cells within the mother have restorative properties and will rush to places like the heart, kidneys, lungs, liver if it’s injured and can even become cells that begin beating. One of the theories I have seen but I don’t know if anyone knows for certain if this is true is that these cells enter our bodies so a ‘host’ is less likely to reject the parasite baby.

#42

not everyone may know is that your genes play a role in determining whether you are more likely to be a morning person or a night owl

#43

I think they know but disregard it but

Just because you date an above average height person doesn’t mean your children will match or exceed the height of the taller person, especially if you’re very short.

#44

Person with a genetics degree here: most of them Autism has more than 200 genes linked to it, both present on autosomes and sex chromosomes. During infection organisms can send small stands of rna to try to regulate genes in the other organism, both as a method of pathogenicity, and as a method of defence. Your genes influence a lot about your future, but not everything, your environment will change expression of your genes, and a diagnosis of a genetic condition doesn’t mean you will experience the same symptoms as someone else with the same mutation as you

#45

For simplicity, let’s say your mother is 50% Chinese & 50% Spanish. That does **not** mean you are 25% of each.

On paper it would seem so but you can have any combination of those two equaling to 50%. It’s not a clean cut in half. It’s a *random* 50% given and 50% not. Although, yes there are dominate genes that can give all the kids a certain nose shape or eye color. Still, you and your siblings might get these DNA combos from mom:

– you: 30% C & 20% S

– brother: 12% C & 38% S

– sister: 5% C & 45% S

So if you ever wondered why your sister looks more Spanish than you its because genetics wise she just is more Spanish.

#46

Trauma can be inherited (look up transgenerational trauma).

So if you feel more sensitive than most people it might be because your grandma experienced something horrible.

On average it takes three generations to heal a trauma if I remember correctly. But only if properly treated and the parents do not retraumatize their kids with their unconscious trauma-responses. This way unhealthy behaviors would become the norm and eventually become genetically preferred automatic behavior for future generations.

#47

Get tested for hereditary high cholesterol (familial hypercholesterolemia). It’s a comparatively common genetic disorder.

It shows next to no symptoms but can clog your arteries and kill you, no matter how healthy your diet and lifestyle. It rarely skips a generation.

The treatment is usually a medication called statins.

#48

One in 40 Ashkenazi Jewish women has a BRCA gene mutation. Mutations in BRCA genes raise a person’s risk for getting breast cancer at a young age, and also for getting ovarian and other cancers. That is why Ashkenazi Jewish women are at higher risk for breast cancer at a young age.

#49

Transposons exist. Some DNA fragments can get cut out of the genome and be inserted in a different part. This can be used in knockout screening: if you introduce a transposon to a bacterium and it grows no colonies, the transposon has inserted itself in a gene that was likely crucial for the bacterium’s survival

#50

Red hair and blue eyes is the rarest hair/eye colour combination

#51

Pretty much everybody is clueless about 99.9% of genetics.

#52

1. Most genetics studies were, and are still, done on white western populations. Some things that we “know” about genetics turn out to not work so well in non-white or non-western populations. Loose example: diagnostic tests to check for certain diseases sometimes misdiagnose Americans with African ancestry, because sometimes we don’t actually know exactly how certain diseases will look in non-European ancestry patients, we just assume it will be the same.

2. Africa, as a whole, is the most genetically diverse continent for human genetics. Humans outside of Africa went through a population bottleneck, resulting in an overall lack of diversity moving forward. The human blender of genetics in Europe just didn’t have many starting ingredients. There are things called linkage disequilibrium maps, which basically map out sections of the genome that are usually found inherited together. In Europe, these maps are quite “chunky”, with large identifiable sections that are sort of reliably found intact. But in Africa, the blender was always running and never had a bottleneck, so those maps are basically a much finer puree, with a lot more mixing. This presents certain challenges, as many studies rely on those maps to make predictions, and it’s harder to do that when the map for Africa as a whole is basically way more complex.

3. Everyone’s cancer is its own unique genetic disease. There is no one true single disease called “lung cancer”, just as there is no one single true human genome. Everyone is genetically unique (yes even identical twins), and every cancer is unique.

4. Chromothripsis is a thing where a chromosome pretty much shatters and gets stuck back together all out of order. And… this is sometimes okay. There are cases of people who have chromosomes that have undergone chromothripsis, and they have mild to moderate symptoms, but they’re not dead, which is miraculous.

5. Remember in biology class when you learn about mitosis? And there’s that step called metaphase where all the chromosomes line up in a line before being separated into two new cells? That spot in the middle of the “X”-shaped chromosomes where the spindles attach to line them up is called the centromere. And it’s sort of mysterious black hole of genetics. There aren’t usually any genes there, just a chaotic cluster-f**k of repetitive sequence that gets chopped forwards, backwards, repeated 7 times, swapped around and repeated again, etc etc in an area that’s hundreds of thousands of nucleotides long. But what’s even crazier is that we don’t really know *why* they are how or where they are, because *you don’t need the wacky wasteland of repeats for them to work*. Almost all centromeres in all animals look like this, but there are exceptions. A very notable exception is that very very rarely in humans, a “mar-del” chromosome can form where a chromosome accidentally loops on itself and pinches (think of that heart thing people do with their thumb and forefinger), resulting in a circular chromosome that still has its centromere, and a “butterfly” chromosome that does not. Without a centromere, a chromosome can’t be duplicated into daughter cells successfully, and cells can’t live without the genes on that butterfly chromosome so this should be lethal if it happens early on in development. But surprise, a centromere can and has spontaneously formed on the butterfly chromosome, making them tiny, viable chromosomes that work pretty much fine! But like I said this is super rare, with only a few recorded cases ever. Centromeres in general are very cool and very mysterious.

6. Everything about modern next-generation genetic sequencing is super interesting, yet not well known to the general public. I won’t brain dump about it, but if you want to know more, ask and I will!

#53

It’s usually taught that bacteria are monoploid (only 1 copy of chromosome) but there are some bacteria that are actually polyploid! It gives them some survival benefits. 

Also viruses can “help each other”. EBV can cause that HIV can infect T-cells but then also B-cells for example, because B-cells will start creating receptors that are normally only on T-cells. 

#54

The mitochondria is the powerhouse of the cell.

#55

The green eyed gene is a recessive gene when compared to brown eyed gene; it is dominant when compared to blue eye gene.