Chapter Content
Okay, so like, let's talk about the stuff that makes us tick, you know? Like, the actual *stuff* of life.
It's kinda mind-blowing, right? If your parents hadn't, like, connected at the *exact* right second - and I mean *exact*, maybe even down to the nanosecond - you wouldn't be here. And if *their* parents hadn't done the same, in the right way, at the right time... well, same deal. You wouldn't exist. And it just keeps going back, right? Parents, grandparents, great-grandparents... all doing the thing at *precisely* the correct moment. Otherwise, poof, no you.
The further back you go, the more ancestors you need. Just eight generations back, which is, like, around the time of Darwin and Lincoln, you're already talking about over 250 people whose unions were essential for *your* existence. Keep going, zoom back to Shakespeare and the Pilgrims, and you've got at least 16,384 ancestors! All shuffling their genes around to, like, miraculously create *you*.
And get this: 20 generations ago? Over a million ancestors! A million! Five more generations and it jumps to over 33 million! And thirty generations back? We're talking over a *billion* ancestors - just counting direct lineage, mind you. No cousins or anything. Just straight back. Over a billion! And if you go back 64 generations, like to the time of Ancient Rome? You're looking at about a *billion billion* ancestors. Which is, like, a zillion times more people than have *ever* lived on Earth. So something's gotta be a little off there, right?
The explanation, which you might find interesting is that your family tree, you know, isn't exactly a straight line. There's gotta be some... well, cousin marriage in there, right? I mean, not directly, obviously. But like, distant relatives on your mom's side marrying distant relatives on your dad's side. It happens. Probably a lot. In fact, if your partner, like, right now, is from the same ethnic group or country as you, there's a pretty good chance you're related in some way. If you look around on a bus, in a park, at a coffee shop, wherever – most of those people? They're probably your relatives. So, if someone brags about being a descendant of Shakespeare or William the Conqueror, you can totally say, "Me too!" Because literally and figuratively, we're all related, yeah?
And, we’re like, surprisingly similar. Compare your genes to almost anyone else’s, and on average, about 99.9% of them are the same. That's what makes us, you know, human. That tiny 0.1% difference - what one geneticist called "about one letter out of every thousand" - is what makes you *you*. There really isn't one single, perfect human genome. Each person's is different. Otherwise, we'd all be exactly the same. It's the constant reshuffling of our genomes that makes us both a bunch of individuals and, like, a single species.
So what actually *is* a genome, anyway? What are genes? Well, let's start with a cell, okay? Inside each cell is a nucleus. And inside the nucleus are the chromosomes. Forty-six bundles of complex stuff. Twenty-three from your mom, twenty-three from your dad. Every cell in your body - like, 99.9999% of them - has the same number of chromosomes. With a few exceptions, like red blood cells, some immune cells, eggs, and sperm. They don't have the full set for various system reasons. Chromosomes have all the instructions needed to build and maintain you. And they're made of long, long strings of this incredible chemical called deoxyribonucleic acid, or DNA, as it's more commonly known. It's been called "the most extraordinary molecule on Earth."
DNA's only reason for being is to make more DNA. And there's a *lot* of it packed inside you. Almost two meters of it crammed into practically every cell. Each unit of length of DNA, consists of, like, 3.2 billion coded letters – enough combinations to make your uniqueness pretty much guaranteed. It's, like, one followed by three *billion* zeros.
Take a good look at yourself in the mirror, and consider this: You have a hundred trillion cells, and practically every one contains about two meters of crammed DNA. So, if you stretched all your DNA out into one long, thin line, it wouldn't just reach the moon and back once or twice. It'd reach it several times. Some estimates say your DNA would be about 200 billion kilometers long.
Basically, your body *loves* making DNA. You can't live without it. But DNA itself isn't alive. Neither are molecules, really, but DNA is *especially* not alive. As one geneticist put it, it's "the most chemically inert molecule in the living world." That's why they can extract it from old bloodstains, old bones, old stuff, you know? And it also explains why it took scientists so long to figure out why this seemingly unimportant thing, you know, this *dead* thing, was so important in the life process itself.
DNA's been around for a *long* time, as a thing that it is. But it wasn't until way back, in 1869, that someone actually *found* it. This Swiss scientist working in Germany, named Johann Friedrich Miescher. He was looking at pus from surgical bandages under a microscope and saw this thing he didn't recognize. He called it "nuclein" because it was in the cell's nucleus. He just noticed it was there at that point. But it clearly stuck with him. Over twenty years later, he suggested in a letter to his uncle that this molecule might be the driving force behind heredity. It was pretty spot on, you know. But it was too advanced for science at the time, so nobody paid much attention.
For most of the next half-century, people thought that DNA played, at best, a minor role in heredity. It was too simple, you see. It was made up of only four basic substances, called nucleotides. Like an alphabet with just four letters. How could you write the story of life with just four letters? Well, kind of like how you can write a complex telegram using just dots and dashes in Morse code. As far as anyone knew, DNA didn't *do* anything. It just sat quietly in the nucleus. Maybe it held the chromosomes together or added a little acidity or something. They thought the complex stuff had to be in the proteins.
But ignoring DNA's role caused some problems. First, there was so much of it. Almost two meters in every nucleus. It clearly had to be doing *something* important. More importantly, it kept popping up in experiments, like a suspicious suspect in a murder mystery. Two studies in particular, with pneumonia bacteria and bacteriophages (viruses that infect bacteria), suggested that DNA's role was seriously underestimated. These experiments showed that DNA had *something* to do with making proteins, which are like, super essential for life. But proteins are made *outside* the nucleus, far away from the DNA. So, like, how was the DNA getting the word out?
Nobody could figure out how DNA passed information to proteins. Now we know that it's RNA, ribonucleic acid, that acts as a translator. See, DNA and proteins don't speak the same language. It's a pretty amazing thing. They’ve been doing a, like, critical double act in the living world for billions of years, but they use totally incompatible codes. Like, one speaks Spanish and the other speaks Hindi. They need a middleman to talk to each other. And that's RNA. With help from ribosomes, RNA takes the information from the DNA in the cell and translates it into a language that proteins can understand, using it to boss the proteins around.
But back in the early 20th century, back when we started this little story, we had a long way to go to figure this stuff out. And to basically understand any of the mysteries of heredity.
It was clearly going to take some pretty inspired experimentation. Luckily, a diligent, talented young guy came along who was up to the task. His name was Thomas Hunt Morgan. In 1904, just four years after Mendel's pea experiments had been rediscovered, he started working with chromosomes. Nearly a decade before the word "gene" even came into being.
Chromosomes, which were discovered more or less by accident in 1888, were called that because they are, like, easy to stain with dyes, and you can easily see them under a microscope. By the turn of the century, it was pretty clear that they played some role in passing on characteristics, but nobody knew *how*. And some people weren't even sure they were involved at all.
Morgan chose this tiny insect called Drosophila melanogaster as his test subject. More commonly known as the fruit fly or vinegar fly or banana fly or, you know, garbage fly. It's like this small, fragile, colorless fly that's always getting into your drinks. As a test subject, fruit flies had some serious advantages. They took up very little space, needed almost no food, could be bred by the millions in milk bottles, and went from egg to adult in just about 10 days. And they only had four pairs of chromosomes, making them easy to work with.
In a small lab at Columbia University in New York - that eventually got the nickname "the Fly Room" - Morgan and his colleagues carefully bred and crossbred, like, millions of fruit flies. Maybe even billions as one biologist had said but that may be too much. Each one had to be, like, picked up with tweezers and watched through a jeweler's magnifying glass for any tiny genetic changes. They tried everything they could think of for six years to create mutants. They zapped them with X-rays, raised them in bright light or darkness, baked them in ovens, shook them violently in centrifuges... but nothing worked. Morgan was almost ready to give up. Then, suddenly, a strange variation showed up over and over: a fly with white eyes instead of red ones. With that, Morgan and his team started to crank out mutations. They could track characteristics to something specific, so they could study the connection between certain traits and specific chromosomes, basically proving that chromosomes *did* play a key role in heredity.
But at the next level of biological complexity, mystery remained. These genes, these DNA things were super hard to study. In fact, when Morgan got the Nobel Prize in the late 1933, many researchers still doubted that genes even *existed*. As Morgan pointed out, it was difficult to reach agreement on "what the genes are – whether they are real or purely conceptual." It's kinda amazing that scientists took so long to accept this thing that's, like, so essential to how cells work. It was so hard to just acknowledge that it’s real!
For a long time, genes were like that. To Morgan’s contemporaries, you know, the idea that you could just pick up a gene and study it was as absurd as, like, a scientist taking out a thought and examining it under a microscope is today.
What was clear at the time was that *something* related to chromosomes controlled the reproduction of cells. In 1944, a team at the Rockefeller Institute in Manhattan, led by a brilliant but shy Canadian scientist named Oswald Avery, did a super tricky experiment that proved, after 15 years of trying, that DNA wasn't just some inactive molecule. By mixing different types of DNA with a non-infectious strain of bacteria, they managed to give it a permanent infectious ability. The proved that DNA was not an inactive molecule, but almost certainly the highly active carrier of information in the heredity process. One biochemist later stated that Avery's discovery deserved two Nobel Prizes.
Unfortunately, one of Avery's colleagues at the Institute, Alfred Mirsky, you know, a stubborn, unpleasant protein fanatic, fought tooth and nail to downplay Avery's work. He even tried to get the people in Stockholm to not award Avery the Nobel Prize. Avery was 66, tired, and couldn't take the stress. So he quit his job and never did research again. But, other research fully proved Avery's conclusions were correct. And soon, a race to understand the structure of DNA kicked off.
If you'd made a bet in the early 1950s about who would win the race to crack the structure of DNA, you probably would have bet on Linus Pauling, the top chemist in America, over at Caltech. Pauling was an incredible genius at figuring out molecular structures. He was also a pioneer in X-ray crystallography, a technique that was super important for figuring out the core of DNA. Pauling was awarded *two* Nobel Prizes. But in the DNA thing, he screwed up by incorrectly thinking it was a triple helix instead of a double helix. The prize ended up going to four British scientists instead.
The most likely designer out of the four guys involved was Maurice Wilkins. He spent a good chunk of the Second World War in a closed room, you know, helping to design the atomic bomb. Two others, Rosalind Franklin and Francis Crick, spent the war with the British government, Franklin with mining and Crick with explosives.
The most unconventional of these four was James Watson, an American, a genius who as a kid, was on the radio show *Quiz Kids*. He was obsessed with the Glass family from Salinger, and some other literature. By 15 he was at the University of Chicago. At 22, he was working at the Cavendish Laboratory in Cambridge. At just 23 years old, in 1951, his hair was a wild mess, and in photographs, you know, he looked like something powerful was pulling him out of the frame.
Crick, 12 years older, didn't even have a doctorate yet. He wasn't as unkempt, but he was a little intense. According to Watson, he was talkative, argumentative, and always wanted people to agree with him. He'd get worked up over the tiniest things. Both of them lacked official training in biochemistry.
Their idea was that if you could figure out the molecular shape of DNA, you could understand, or so they hoped, how it did everything it did. They seemed to be trying to do as little work as possible. As Watson put it in his autobiography, *The Double Helix*, "I wanted to learn about the gene without ever learning any chemistry." They weren’t exactly told to work on DNA, and for a time, they were told not to. Watson would say that he was studying crystallography, and Crick claimed he was finishing a paper on X-ray diffraction for large molecules.
In the common explanation of cracking the DNA puzzle, Crick and Watson get the all credit, but their breakthrough was built on the work of their rivals. Some historians have called that work an "accident." At least at first, Wilkins and Franklin at King's College were far ahead of the curve.
Wilkins, a New Zealander, was really reserved, almost to the point of invisibility. He shared the Nobel Prize for DNA structure with Crick and Watson in 1962. But in a 1998 PBS documentary about the topic, he got barely any screen time.
Rosalind Franklin was the most mysterious of the bunch. In Watson's *The Double Helix*, he describes Franklin, like, harshly. She was, you know, uncooperative and secretive, and she was purposely unfeminine which, apparently, bothered Watson. He thought she "was not unattractive and might have been quite stunning had she taken even a mild interest in her clothes.” But she seemed determined to disappoint, and she wasn't even wearing lipstick, which perplexed him. Her clothing style was “the uniform of English research students.”
Franklin had the best pictures of DNA structure that she got through X-ray diffraction. Linus Pauling made the technique what it was, and it had been used to study atoms in crystals before - making "crystallography" a thing, but DNA was trickier to get a handle on. Franklin got good results from it, and that made Watson angry. Because Franklin didn’t want to share her findings, she was very secretive with her discoveries.
Franklin had good reason not to share her findings. In the 1950s at King's College, female researchers were held back by prejudice. No matter how high their position, they couldn’t go to the senior common room. They had to eat in some like, dingy room instead. Watson said that it was “grim and depressing”. She was constantly being pushed - even harassed - to share her research with the three men who wanted her work, but not respect. As Crick himself admitted later, "I'm afraid we always tended to adopt... what's the best word for it... a patronizing attitude towards her." Two of them were from a competing lab at King's College, and the other one basically took sides with them. Franklin’s keeping her work locked away wasn’t too surprising, you know?
Wilkins and Franklin didn't get along with each other, and Watson and Crick seemed to use that to their advantage. Even though Crick and Watson were taking liberties in Wilkins' domain, Wilkins ended up siding with them. It wasn’t the weirdest thing because Franklin was acting kinda weird, too. Her research indicated that DNA was definitely a helix. And Franklin denied it! Watson was shocked and embarrassed, and in the summer of 1952, Franklin put up a notice on the door to her lab in the physics department where everyone could read that "It is with great regret that we have to announce that the D.N.A. helix is dead as of Friday 18th July 1952... It is hoped that Dr M.H.F. Wilkins will give a suitable speech in memory of the double helix."
As a result, in January 1953, Wilkins showed Watson a picture of Franklin's X-ray diffraction of DNA. He did it "without either informing her or obtaining her permission." That was a major help. Watson acknowledged that this was “the key event... It greatly stimulated us.” Knowing the general shape of the DNA molecule and some other key pieces of data, Watson and Crick stepped up their work. And things fell into place pretty quickly. At one point, Pauling was going to be in England for a conference where he might have bumped into Watson and figured out, you know, what he had been doing wrong with the DNA. But because it was the McCarthy era, a commie was not allowed to travel abroad, so Pauling was stuck in New York, and they took his passport. In contrast, Crick and Watson had the advantage that Pauling's son was working at the Cavendish Laboratory. And he was innocent enough to share his father's successes and failures as they occurred.
Watson and Crick knew they could be beat at any time, so they put everything into solving the problem. It was already known that DNA contains four chemical elements – adenine, guanine, cytosine, and thymine – and they’re always in special pairings. Watson and Crick played around with pieces of cardboard cut into molecule shapes, and they figured out how they connected with one another. Using this, they created a model of the DNA double helix. It was probably the most famous model in modern science. With bolts that connected the metal pieces to make the shape of a helix. They invited Wilkins, Franklin, and everyone else to see it. Everyone in the field could see they had solved the problem. It was great detective work, even if it was unfair to Franklin.
On April 25, 1953, *Nature* magazine ran Watson and Crick’s 900-word article called “A Structure for DNA.” Two articles from Wilkins and Franklin also appeared in the same magazine. The year was full of major events, like Edmund Hillary trying to summit Mount Everest. And Elizabeth II was about to be crowned Queen. Because of these events, the DNA thing was basically ignored. It got a quick mention in a newspaper, and it was it.
Rosalind Franklin wasn't around to share the Nobel Prize. She died of ovarian cancer in 1958, just four years too soon to be given the prize. She was only 37. Her cancer was probably a result of long-term exposure to X-rays. In one biography, it says that Franklin rarely wore radiation shields and she carelessly walked in front of the X-ray machine. Oswald Avery didn’t get a Nobel Prize either, and he's mostly forgotten about. But at least he knew that he had been proven right before he died in 1955.
Watson and Crick’s discovery didn’t get completely affirmed until the 1980s. As Crick said in one of his books: “It took 25 years for our model of DNA to go from being thought probably right to almost certainly right... and finally to being certainly right.”
Even with the structure of DNA understood, genetic research made swift advances. In 1968, *Science* magazine was bold enough to run a piece called "Biology Is Molecular Biology." Genetics was almost done, as unlikely as that sounds.
Actually, that was the beginning. Even today, we still don’t understand DNA. Like, why does so much DNA seem to do nothing? Ninety-seven percent of your DNA is this, you know, junk or what biochemists call “non-coding DNA”. Only some parts of each part work to manage and organize things. They’re these weird, hard-to-understand genes.
Genes are just instructions for making proteins. That’s what they do. They’re like keys on a piano. Each key only plays one note. Kind of boring. But, like, put them all together, and you can make an incredible symphony, which is the human genome.
The genome is the how-to manual. So chromosomes are like chapters in a book, and genes are the instructions for making proteins. The words written in the instructions are called codons, and the letters in each word are bases. The bases, the DNA alphabet, are made up of the four nucleotides: adenine, guanine, cytosine, and thymine, yeah? Even though they’re super important, they’re not exactly rare. For example, guanine is named because there’s a lot of it in bird guano.
DNA looks like a spiral staircase or a twisted rope ladder, the famous double helix. The sides of the structure are made up of sugar called deoxyribose. That makes the whole double helix a nucleic acid - giving it the name "deoxyribonucleic acid". The rungs - or steps - are made of two bases linked together. The bases only pair up in two ways. Adenine always pairs with thymine, and guanine always pairs with cytosine. As you go up and down the ladder, the order of these letters make up the DNA code. And that code has been the goal of the human genome project, you know, recording the codes.
The most amazing part about DNA is how it makes copies of itself. When a new DNA molecule is needed, the two strands split down the middle, like a zipper on a jacket. Each strand halves into a new pair. Because each nucleotide on one strand matches a specific nucleotide on the other, each strand serves as a template for making a new strand. If you only have one strand of your DNA, with the right components, it would be easy to build the other one. If the first step on one is guanine, you know it has to have cytosine on the first step. By following all the nucleotides pairings up the steps, you’re going to have a new molecule. It all happens really, really fast, in a matter of seconds.
In most cases, our DNA replicates very precisely, but very occasionally - like, about one in a million times - a letter, a base, ends up in the wrong spot. It’s called a Single Nucleotide Polymorphism, or a snip. A snip is buried in the non-coding DNA strand and doesn't really have an impact on the body. But, occasionally, snips do something. They can make you likely to get a specific disease. They can also have a tiny little beneficial thing, like more protective skin, or more red blood cells for someone living at a higher altitude. Those little variations keep accumulating, which causes variations between people and populations.
In DNA replication, both accuracy and variation have to balance one another. Too much variation, and the organism won’t work. Not enough variation, and it won’t adapt. The same has to be true for an organism’s stability and innovation. More red blood cells in a person or people who live higher up can help them move and breathe more effectively because they can carry more oxygen. The more red blood cells there are, the more concentrated the blood becomes. More blood cells make the blood “like petroleum”. That puts a strain on the heart. People living in the highlands also need more lung capacity, which also makes them more likely to have heart disease. Darwin’s natural selection guards us and helps explain why we’re all the same. Evolution doesn’t make you so unique that you become a new species or something.
The point one percent of gene variation between you and me is decided by snips. When you compare your DNA to a third person, about 99.9% of you is the same, but all the snips will most likely be in other places. If you compare more people, you'll have even more snips in different places. You can have up to 3.2 billion bases where the code for someone or a group of people on the Earth is different. So, not only is it inaccurate to say “the” human genome, there really isn’t "a" human genome. There are 6 billion of them, even though 99.9% is the same. But, like, you can also say, as David Cox said, “You can also say that no one has anything in common.”
We still have to explain why there's so much DNA without a purpose. At first, the answer can be discouraging, but the reason that life seems to exist is so the DNA can exist. 97% of the DNA is called Junk. It's made up of letter blocks. They "exist purely and simply because they are good at copying themselves." To say it another way, 97% of your DNA doesn't serve you. It serves itself. And you exist to assist the DNA, not the other way around. You probably recall that life wants to exist, and that life lies in the DNA.
Even though DNA contains the instructions to make genes - as scientists say, the genes are coded for- its purpose isn't necessarily to keep the organism working well. There's one gene in our bodies, a protein called reverse transcriptase, that has no known good side. In fact, it allows retroviruses like HIV to sneak into the human body.
To phrase it another way, our body puts a lot of effort into making proteins that don't help anything and can sometimes deliver a lethal blow. But, our body has to, because the genes instruct it to. We’re like, basically, the land where they run wild. By what we can tell, almost one half of human genes only copy themselves.
In one sense, all organisms are slaves to their genes. That can explain why salmon, spiders, and plenty of other things die when they’re mating. Wanting to reproduce and to carry on the genes is one of the most powerful impulses in nature. As Sherwin B. Nuland said: “Behind imperial dissolutions, the hatching of the self, the writing of majestic symphonies lies the imperious need to be satisfied.” From the evolutionary perspective, sex essentially exists to promote the act of handing off the genes.
The fact that much of our DNA does nothing took long for scientists to accept. Since then, new and more unforeseen discoveries have been made. First in Germany, and then in Switzerland, scientists conducted a string of weird experiments that produced shocking results. They placed the genes that controlled how mouse eyes developed into fruit fly larvae. They expected to see something interesting and different, but mouse eye genes not only led to mouse eyes in fruit flies, but also to fruit fly eyes! It had been 500 million years since the two animal species had had ancestors in common. But they were able to exchange genes like sisters.
The same thing was going on everywhere. Researchers put human DNA into some cells of fruit flies. And the flies accepted it like it was theirs. It turns out that more than 60% of human genes were basically the same as those in fruit flies. At least 90% of human genes were related to the genes in mice. We even have the same genes that would help us grow a tail, if they were able to be activated. In one area after another, what scientists were studying didn’t matter. Whether they were researching nematodes or humans. The genes were essentially the same. It looked like all of life grew from the same plan.
Scientific research has also revealed a group of master genes. They control the development of a specific part of the body. These are known as homeobox, or Hox, genes. They answer the age-old question about how all of the many billions of embryonic cells that grew from one single fertilized egg which carry the same DNA would know which way to go and what they were meant to do, like what made one become a liver cell, one an elastic neuron, and yet another a blood sac. Apparently, the Hox genes told them what to do. The Hox genes issue the same instructions to all organisms.
Genes and their order do not always reflect the complexity of an organism. Or, in general, not all. Humans have 46 chromosomes, but a few ferns can have up to 600. Lungfish, one of the least evolved of all the animals, have 40 times more chromosomes than we do. Even the average water newt has five times more genes than us.
Clearly, the most important thing isn’t the number of genes you have, but what you do with them. Human gene quantity has gotten more attention recently, and that’s a good thing. Not long ago, many thought that humans had at least 100,000 genes. But initial findings from the Human Genome Project led to the number being greatly reduced. Research indicates that humans only have about 35,000-40,000 genes. Which is, like, the same as grass. The result was both surprising and a bit disappointing.
It’s likely that you’ve seen genes associated with diseases. Scientists have happily stated that they’ve found the gene that makes you fat, schizophrenic, homosexual, criminal, violent, an alcoholic, or a thief. One high point, if you could call it that, was in 1980 in *Science* magazine. It emphatically stated that women’s genetic makeup predetermined that they had low math ability. What we know now is that no aspect of you is that simple.
In one key way, this is a bummer. If you had one gene that decided how tall you are, or whether you had diabetes or went bald, or anything that was obvious, you could easily separate them and cure them. Unfortunately, 35,000 genes, working solo, aren’t enough to make a complex human body. Clearly, the genes have to work together. There are some physical and mental disorders, like hemophilia, Parkinson’s, Huntington’s, and cystic fibrosis, that are caused by single bad genes. But normally, according to natural selection, they’re eliminated before they can cause damage to all of mankind. Thankfully, most of our fate, is decided not by genes, but the way the genes all work together. As such, it’s not surprising that we don’t fully grasp how they all come together as a group, and that we can’t design our own babies anytime soon.
What it comes down to is the more research we do, the more we don’t know. Tests have shown that even your thoughts can affect the way the genes work. For example, the speed that a man's facial hair grows depends a bit on how much they think about sex. And some researchers in the 1990s took it even farther. They found that with some experiments on key genes on embryonic mice, after they were born, they weren’t just as healthy, they were sometimes even healthier than the non-experimented siblings. What it turned out was that after a key gene was damaged, another would come in and fill the spot. That’s a great thing for us as organisms, but it’s bad for figuring out the cells work. It just makes things that we’re barely starting to understand all the more complicated.
It was precisely this intense complexity that made work on cracking the human genome appear only to be the beginning. As Eric Lander, from MIT, said, the genome is like a part list: it tells us what we are made of, but not how it works. What we need now is an operation manual, instructions on how to make it function. That's still a long way away.
So, as a first step, we're gonna crack the human proteome. It’s a really new concept. The word proteome didn’t even exist ten years ago. The proteome is a library of all the data to create proteins. "Unfortunately," said *Scientific American* in the spring of 2002, "the proteome is far more complicated than the genome."
You could say that. You probably remember that proteins are the workhorses of the entire system. Every cell has about 100 million proteins working all day long. There's so much going on, it's impossible to grasp. To make it even worse, how proteins act and what they do don’t just depend on their chemical nature like genes, they also depend on their shape. A protein has to have elements that come together the right way. Then it has to fold into a very specific shape to function. That word "fold" is kind of confusing. It makes you think of a precise shape, which isn’t exactly right. The shape is a random mess. It’s not that much like a folded towel as it is like a mass of hangers.
To add to it, proteins are flirts of the biological world, as I like to say. If you are drunk, they can phosphorylate, glycosylate, acetylate, ubiquitinate, sulfonate, and do all sorts of other things. It doesn’t seem to take that much to get them to change. According to *Scientific American*, drinking a glass of beer significantly changes the quantity and type of proteins in your system. Even though that’s great for alcoholics, it doesn’t help geneticists that want to understand how it all works.
Everything has the potential to be unbelievably complex, and it all actually is, to an extent. But, it all comes down to one simple thing. How life functions is all the same. All of the slight and skilled chemical processes that keep cells alive, everything to do with the coordination of nucleotides, the carrying of information from DNA to RNA have only evolved one time in nature. And it’s remained largely untouched ever since. As Jacques Monod, a French geneticist, joked: “What is true for E. coli is true for the elephant only more so.”
All organisms grew from the same original plan. We, as humans, have only grown more fully. We’re all just a 3.8-year-old, moldy record, with endless twists, alterations, changes, and repairs. And we’re, like, surprisingly similar to fruit and vegetables. About half of all the chemical reactions that occur in a banana are the same as the reactions that happen in you.
It can’t be overstated enough. All life is related. Now and, it's thought, forever, the truest confession in the world.