Why Do Humans Have Less DNA Than This Flower?
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Why Do Humans Have Less DNA Than This Flower?


Human DNA consists of 23 pairs of chromosomes
with over 3 billion nitrogenous base pairs. Surely we don’t need all that to function
right, I mean, how hard can it be? Hey there peoples, Julian here for DNews.
I’m sure what I’m about to say is review for many of you but just to make sure everyone’s
on the same page I’ll reiterate: you need DNA. Red blood cells being the exception,
all the cells in your body have it. For most of those cells you have 23 pairs of long DNA
sequences called chromosomes. The DNA is structured like a spirally ladder and the rungs of these
ladders are the nitrogenous base pairs Adenine and Thymine, and Guanine and Cytosine. You
repeat and rearrange those 4 bases enough and bingo, you got yourself the blueprint
to build a human being. Or a potato. How you arrange them is key. Ok, everybody up to speed?
Great. So just how many base pairs do you need? For
a human, not a potato. When we examine our 23 chromosomes it would seem the answer is
a little more than 3 billion. Three billion ATGCs to make a Steve. A potato only has only
840 million base pairs by comparison, and that makes sense right? Steve is a pretty
complex guy, certainly more so than a potato. Though interestingly the potato has 24 pairs
of chromosomes to our 23, they’re all just a lot shorter. But don’t be mislead into thinking that
more DNA=more awesomeness. An organism with a genome 50 times bigger than ours isn’t
going to necessarily be a telepath or have laser vision or the power to control magnetic
fields or an increased healing factor. It could be something as simple as a flower.
Actually it is. At over 150 billion base pairs in length, the flower Paris japonica is the
largest genome ever accurately measured. The ameboid Polychaos dubium was estimated to
be even bigger, at 670 billion base pairs, but it’s claim to the throne is disputed
because the techniques used to measure genome size in the 60s have since proven flawed. It’s not the size of the DNA, it’s how
you use it. At the other end of the spectrum there are bacteria with genomes that don’t
even break a million base pairs. Nasuia deltocephalinicola has the smallest genome ever discovered, measuring
in at just 112 thousand base pairs, though it needs to live in symbiosis with another
bacterium to survive. Nanoarchaeum equitans gets by with a scant 490 thousand base pairs
encoding 540 genes, it’s the smallest independent cellular unit discovered yet. Scientists recently
synthesized a minimalist genome of just 530 thousand base pairs that encode just 473 genes
by whittling away 70 thousand base pairs of the already diminutive Mycoplasma genitalium. That’s right, organisms can live without
all their DNA. In fact it’s estimated that you’re only using about 8% of your genome.
1% of it is coding proteins, 7% is regulating when to use that first 1%, and the remaining
92% is just junk as far as we can tell. That number is disputed, and by a different measurement
and the loosest definitions as much as 80% of our DNA may serve some function, but that
still means 60 million base pairs are just along for the ride. Evolution provides a good
explanation for why we’re carrying around all this extra baggage: becoming human was
a long and messy path. Along the way some DNA is going to mutate into disuse but keeping
it around won’t be too much of a hassle. In fact having all that extra ATGC to work
with means mutations are less likely to occur on an essential gene and therefore won’t
be catastrophic. It may actually be beneficial, giving random chance the opportunity to mutate
junk DNA* into something useful and giving an organism an edge. As a bonus the process
of evolution explains why a flower can have 50 times more DNA than we do. Just how much of your DNA is junk is still
up for debate. It may actually be used to make important things, like your face. Anthony
Carboni explains here. Are you surprised about your genome being
bloated or is it no big deal to you?

100 thoughts on “Why Do Humans Have Less DNA Than This Flower?

  1. More research is needed. Oh and it's totally worth mentioning that we haven't a clue how the missing DNA would impact us (we don't even know how missing DNA affected the modified organisms).

  2. It's a lot like programming – a program might involve 50k lines of code, but remove all the comments, white-space, redundancies, and inefficient methods and you might be able to reduce it to less than 20k.

  3. Now i know this video was inspired by the TV show duck quacks don't echo, i don't now how else they coincided to close to each other.

  4. There's no junk DNA. The strands are physical realization of Turing Machines. They are the first, and yet the most advanced computing devices.

  5. I hate to disagree (not true) but by increasing the size of the DNA you also increase the chances a mutation will occur. If you do a lot of steps you have more area to go wrong. I assume there's a % chance that something will mutate per nucleotide and adding more useless nucleotides wouldn't per say make the other useful. It's possible that those genes possessed some use for our ancestors (as you said) and simply mutated out through chance. And, I don't know about you, but I'm unaware of anyway to remove genes from a genome. If each gene codes for a new amino acid then in theory things with more genes are more complex, but that's not true if the genes are turned off. My opinion is that it's just easier to turn the genes off then go to the work of removing them. It would explain why incredibly simple organisms have incredibly long genomes, but that is 100% a guess. What do I know?

  6. I'm sure that most of the "junk" DNA serves valuable functions. Some of it may only be active for a few vital hours during embryonic development, never to be active again. Also, at the molecular level, plants and other "simple" organisms can be more complex than us.

  7. Any programmer knows that timing of functions is very important. So having base pairs which seem unused may be timing/delay functions which modulate gene expressions elsewhere.

  8. Junk DNA is a fairy tail. Read "Junk DNA" by Nessa carey
    Evolution is a fact. But Neo Darwinism is false. DNA is a code. Read "Evolution 2.0" by Perry Marshall

  9. That's not junk DNA, this so called junk DNA plays a very important role during the development of the fetus.

  10. Please write down the numbers you talk about, numbers are specially hard to understand for non natives. By hard I mean we have to pay extra attention to "decifer" them. It is something like metric system vs imperial (that you already cover, good job there).

  11. i simply HATE it when people over emphasize the "E" in nitrogEnous or homogEnous. its shit like this that cause mass shootings

  12. Having more junk DNA so that mutations are less likely to occur on useful DNA is like buying two ice-creams just in case one melts. Decaying follows 1st order, not zero order kinetics.

  13. I feel like e should set up a website for Julian so he can afford more food.
    You lookin like a Heroin addict Jules

  14. Check out this thing! Oh but this thing was proved wrong in the 60's so it really doesn't matter…

    Then the rest of the video that we didn't click for….

  15. I'm sure all of our DNA does something, we're just not sure what it does. We used to think the same thing about our brain, but that's been proven false.

  16. That extra stuff is back up files… The more and more you learn about the human bio the more and more you realize how critical tweeks could be

  17. "As a bonus the process of evolution explains why a flower can have 50 times more DNA than we do." — I am still waiting for an explanation.

  18. Think your show is great!
    Just some constructive criticism: Signs your information is about the level of upper secondary school, maby listing so many organisms base pairs and things like that make the audience (who is supposedly young) lose interest. I'm not telling you to dum it down! I'm just saying to keep it light while informative, or "fun" if you will…

  19. Nature doesnt do things it doesnt need to do, there is no such thing as "DNA we dont need", more accurately it is "DNA we dont understand".

  20. Junk DNA? Really? Just, really?! O-o sigh

    We need to stop using such outdated, misleading terms, it's inaccurate and leads to confusion. It has long since been disproved that non-coding DNA is not junk and has many essential functions in the genome. We are just beginning to scratch the surface of what all of the genome really does and how it all works together.

    Hey D news, can you make a video on why the term "junk DNA" should be scrapped?

    Speaking of another piece of outdated information that really needs to stop being put into biology textbooks, two blue-eyed parents can have a brown-eyed child, no mutation needed.

  21. 80% of our dna is junk? It's like what the old Egyptians said about the human brain; a useless organ xD
    2016 guys <3

  22. Just have to point out a logical fallacy in the monologue. There is a certain percentage chance that any base pair will spontaneously mutate. Having more DNA around doesn't change that percentage at all. Think about it … raindrops fall randomly on your sidewalk. Does having a bigger sidewalk make it less likely that raindrops will fall on the part where you walk?

  23. I doubt that DNA is actually bloated. Its much more likely that the arrogance and egos of the researchers, is what is actually bloated. Just because we do not understand something or know its function, does not necessarily mean that there is no function.

  24. What is really amazing is that Japanese people have 15% less junk DNA than the rest of humanity. Perhaps they were a contrived people. You know, like Cylons.

  25. The term "junk-dna" is being discarded since we are identifying that all that extra dna may provide critical context to the protein coding genes. Poor job Dnews and Discovery

  26. I wish he would just PUSH his glasses all the way on his face. The SHADOW on his face EVERY EPISODE bothers the shit out of me..

  27. DNA that you don't understand yet is not junk that does nothing just because you don't know what it does. Unlike Einstein, the average professional scientist is actually an idiot.. void of creativity and on par with the dumbest of humans, just with good memories to log info they read and regurgitate it as they are told to, without any uniqueness or inspiration or imagination. It's sad to know the scientists of today are as simple minded as the ones who were convinced the earth was flat or the sun revolved around the earth or that DNA doesn't do anything just because they cant tell what it does.

  28. So its not junk DNA because enhancers, and a flower has a lot of junk because it went through more evolutionary cycles than the modern human even though it didn't? Soooo no concrete answers…

  29. see you next time in dnews i thought it was seeker and are you guys going to continue promoting your old videos that you guys sold to Now This

  30. Yes yes. Our other 92 percent can be thought of like potential energy. We can either utilize it, or breeze past it. To choose either a vital or sedimentary lifestyle

  31. Beginning to think about "pulp science" for the various videos, and reading these comments, and thinking "pulp comments" none of them really worth the paper they are written on… Apparently "The quality of a comment is inversely proportional to the effort it takes to write it!"

  32. So are you saying roaming human parasites have less DNA, even though they have the same number of chromosomes than their victims… Therefore, the criminal gene doesn't exist, though rather is a lack of a gene or genes in one or more of their 46-chromosomes? Bet you a 5er that the missing genes are from the Pineal bundle of chromosomes?

  33. since animals are mobil they need lees complication to be mobil so theres less dna. maybe thats why cancer happens as a result

  34. Wouldn't most of that "junk* have been used for initial development? After the dna that grows the fetus has done its job it's sits idle…maybe?

  35. We Love It: lets us learn how we can change our daily lives to influence our genes for our offspring!!!

  36. Give honor and praise to whom it is due, to God. There is no such thing as evolution. Even with today's understanding, people still choose (willingly) to reject God, how sad.

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