DNA to Dysfunction: A Crash Course in How Your Body Builds (and Botches) Its Biology

Let’s Start at the Very Beginning (A Very Molecular Place to Start)

If you’ve read the last post, you know collagen is a big deal. But it’s not a mystery, it’s made, step by step, like every other protein in your body. Even a tiny glitch can cause a lot of problems, especially in tissues like skin, joints, and blood vessels where collagen does the heavy lifting.

This post walks through how proteins like collagen are built from DNA to folded, functional molecule, and how small missteps can lead to big problems.

We talk a lot about genes and proteins in the EDS world, especially when it comes to collagen, but what does those words actually mean? How does your body go from a string of DNA to something that’s supposed to hold your tissues together?

In this post, we’ll walk through the steps clearly, and without jargon overload, so you can understand how things are supposed to work…and what might be happening when they don’t.


🧬 What Is DNA, Really?

Glad you asked! This is hands down my favorite topic. I literally have it tattooed on my body. DNA double helix tattoo

Yes, that’s a DNA double helix inked on my leg. It’s not just decoration but a daily reminder of how deeply this molecule shapes our lives, and why I dedicated my career to genetics! Bonus: Who can figure out the significance of this particular DNA strand?

Ok, back to science!

DNA (short for deoxyribonucleic acid) is your body’s instruction manual. It’s built from four nitrogen bases, each one represented by a letter:

  • A = Adenine (green in many sequencing traces)
  • T = Thymine (red)
  • C = Cytosine (blue)
  • G = Guanine (yellow or black)

These bases pair up in a predictable way (A with T, C with G) forming the rungs of a spiraling ladder known as a double helix. But this ladder isn’t just structural or elegant for its own sake. The order of those letters forms a code, a molecular script that tells your body how to make everything it needs. Collagen? Insulin? Neurotransmitters? Enzymes? Entire organs like your liver, or limbs like your arm? They all start with DNA!

Fun Fact: Every cell in your body (except red blood cells) contains about 2 meters of DNA folded into a space smaller than the tip of a pin. To make that possible, DNA wraps tightly around proteins called histones, forming a coiled structure known as chromatin. That chromatin twists and condenses even further into dense bundles called chromosomes, those iconic X-shaped structures you might remember from biology class.

Humans have 23 pairs of chromosomes, one from each parent, for a total of 46 chromosomes. Each one functions like a volume in a massive biological encyclopedia, and each contains thousands of genes, or individual entries packed with instructions. Together, these 46 chromosomes make up your body’s reference library: the full set of blueprints for how to build and maintain your body.

A mutation in just one gene is like a typo in a single line of a complex manual. It might be minor, or it might change the outcome entirely. Whether it disrupts a key structural protein or throws off timing and regulation, even one small change can echo outward through the whole system.


🧩 What’s a Gene?

A gene is a segment of DNA with a purpose. While your full DNA library holds every instruction your body might ever need, a gene contains just one specific message: how to make a particular protein. A single recipe within a massive cookbook.

Genes aren’t one tidy block of information, though. Most are split into several exons, which carry the actual coding information, and introns, non-coding sequences interspersed in between (Not Junk DNA! But I'll save that rant for another day...). Before the cell can use a gene, it has to process this draft, cutting out the irrelevant parts and stitching together the useful ones.

To accomplish that, the cell first transcribes the DNA into a working copy called RNA (short for ribonucleic acid). RNA is like the field-ready version of the genetic blueprint, usable, flexible, and ready for action. Once that RNA copy is made, the cell can begin translating the message it carries into a functioning protein, turning code into biochemistry! This process happens in two key steps: transcription (making an RNA copy) and translation (assembling the protein from that RNA code).


✏️ Step One: Transcription

Inside the nucleus, a special compartment in the cell where your DNA is stored, an enzyme called RNA polymerase unzips the DNA, pulling apart the two strands of the helix so it can read the instructions and make a temporary working copy of a gene. In this RNA version, uracil (U) is used instead of thymine (T), a small but important difference between DNA and RNA. That copy is called messenger RNA (mRNA), a single-stranded version of the gene. mRNA is made up of codons, which are sets of three RNA letters that act like molecular instructions, each telling the cell which building block (amino acid) to add next. With four bases and three-letter combinations, there are 64 possible codons, but only 20 standard amino acids. Therefore, many amino acids are matched to more than one codon. This gives the system a bit of built-in flexibility, which can help protect against minor errors. In addition, there is one start codon (AUG, which codes for methionine) and three stop codons (UAA, UAG, UGA), which signal the end of a protein and do not code for any amino acid. 🔍 Want to see the full codon-to-amino acid table? Codon Table

📌 Enzymes are specialized proteins that make chemical reactions happen faster and more efficiently.

Before it can leave the nucleus, the mRNA goes through a process called splicing. Genes are made of coding segments (exons) and non-coding ones (introns). Splicing cuts out the introns and stitches the exons together, turning the raw transcript into something readable. If this editing step goes wrong, like with a splice-site mutation, the resulting protein can be too short, too long, scrambled, or otherwise completely nonfunctional.

The mature mRNA then exits the nucleus into the cytoplasm, the cell's busy, fluid interior where protein building happens.


📖 Step Two: Translation

In the cytoplasm, the mRNA attaches to a ribosome, a molecular machine that reads the codons and assembles the correct amino acids in the right order. tRNAs (transfer RNAs) are specialized RNA molecules that act like couriers, delivering the amino acids that match each codon to the ribosome for incorporation.

The ribosome is like a molecular assembly line, it reads the mRNA and builds the protein one block at a time. The amino acids are linked into a growing polypeptide chain. This precise sequence becomes the protein’s primary structure.

This step is critical for collagen. If the codon sequence is off or misread, the resulting protein won’t form the proper structure.


🧠 Folding: From String to Structure

Once the chain is built, it begins folding into a 3D shape, its secondary and tertiary structures. This folded shape will determine whether the protein functions, structurally (like collagen), enzymatically, or hormonally.

📌 Structure = function. If the folding goes wrong, so does the protein.

Other specialized proteins called chaperones help guide the folding process, especially when the cell is under stress.

Some proteins go even further and form a quaternary structure, where multiple folded chains assemble. Collagen’s triple helix is one such example, beautiful and strong when built correctly, but weak when misfolded.


🛠️ Post-Translational Modifications

Proteins may need final chemical touch-ups to become fully active. Here are some of the most common post-translational modifications:

  • Hydroxylation: Adds tiny chemical tags that help collagen molecules stick together and maintain their strength, especially under stress. Without this modification, collagen strands can become unstable or weak.
  • Glycosylation: Attaches sugar molecules that act like name tags or protective armor, guiding the protein to the right place or shielding it from damage.
  • Cleaving: Snips off unnecessary sections so the protein can take its final shape or turn on its full function.
  • Cross-linking: Forms sturdy chemical bridges between parts of a protein, or between separate protein strands, helping tissues stay strong and hold their shape under stress.

These steps need non-protein cofactors like vitamin C, iron, and copper for the biochemical reactions to occur. If even one step fails, the final protein may be fragile or dysfunctional, even if the gene itself was fine.


🧪 What Happens When There's a Mutation?

Mutations are changes in the DNA code that can alter how the body reads or interprets its genetic instructions. Some mutations cause major disruptions and others are barely noticeable. A single altered base can have downstream effects that ripple from gene to protein and beyond.

Here are the most common mutation types:

  • Missense: One letter swap that changes a single amino acid. The outcome depends on where and what.
  • Nonsense: Inserts a premature stop signal, cutting the protein short.
  • Frameshift: Adds or deletes letters, disrupting the entire downstream code.
  • Splice-site: Interferes with how introns are removed from RNA.
  • Indel: Small insertions or deletions that often mimic frameshift effects.
  • Translocation: Shuffles chunks of DNA, potentially splitting genes or misregulating expression.

Each mutation type can effects different steps in this tightly regulated system. A small change in DNA might result in a misread RNA message, a malformed protein, or one that never gets made at all. When these missteps involve collagen or other structural proteins, the consequences can echo widely through connective tissue, joints, and organ function, as discussed last time.

It’s important to distinguish mutations from single nucleotide polymorphisms (SNPs), naturally occurring variations found throughout the population. Most SNPs are benign and simply reflect genetic diversity, kind of like alternative spellings of the same word. But occasionally, even a harmless-looking SNP can influence how a gene is regulated or how a protein behaves, depending on its location and context.

The need for knowing these steps isn’t just for academics. They’re a real-world map of where things can go wrong. In hEDS, no single causative mutation has been identified yet, but researchers suspect the problem lies somewhere along the pathway from gene expression to collagen protein assembly. Understanding that biochemistry helps connect the dots between invisible changes in your biology and the obvious symptoms they produce.

(Hint: if you’re paying close attention, somewhere in this post you already have what you need to crack the code. DNA → codons → amino acids → spell it out...)


💡 TLDR

Quick recap:

  • DNA: The original blueprint, stored in the nucleus. It holds the instructions for making every protein your body needs.
  • Genes: Segments of DNA that each code for a specific protein. Think of them as individual recipes in your cellular cookbook.
  • Transcription: The cell copies a gene into messenger RNA (mRNA), a working version of the instructions.
  • RNA Editing (Splicing): Introns are removed, and exons stitched together. Only the useful parts move to the next step.
  • Translation: The mRNA is read by a ribosome, which builds a chain of amino acids based on the codon sequence.
  • Folding: That amino acid chain folds into a three-dimensional shape. Structure is everything and folding determines function.
  • Post-Translational Modifications: Chemical tweaks like hydroxylation or glycosylation refine the protein for proper performance.
  • Cofactors: Helpers like vitamin C, iron, and copper enable key modification steps. Missing one? The whole process might stall.
  • Mutations: A single typo in the genetic code can derail any part of this process, from faulty instructions to a misfolded or unstable protein.

These steps build the proteins that hold your body together. When they work, your biology runs smoothly. When they don’t, things fall apart.


❤️ Final Thoughts

Understanding your body at the molecular level isn't just for scientists, it's for anyone who's ever been told "we can't find anything wrong" when something clearly is. These processes, from DNA to protein, shape how we move, heal, and feel.

For those living with complex conditions like hEDS, this knowledge is more than just interesting. It's validation. It's proof that even when the usual tests come back normal, the complexity beneath the surface matters.

You don’t need to memorize every term. But if you understand the big picture, that your body builds proteins step by step, and that each step can go subtly off-track causing huge ripple effects, then you’re already ahead. You have the language to advocate for yourself and the insight to ask better questions.

So here’s the takeaway: your biology tells a story, not just of what’s happening, but how and why. The more fluent you become in its language, the harder it is for others to dismiss what you're feeling. And the more you understand, the better equipped you are to stand up, speak out, and push for care that actually accounts for the full picture.


🔗 References

  1. Alberts B, Johnson A, Lewis J, et al. Molecular Biology of the Cell, 6th ed. Garland Science, 2014.
    Foundational textbook covering the central dogma of molecular biology, including DNA structure, gene expression, protein synthesis, folding, and regulation.
  2. The Structure and Function of DNA – NCBI Bookshelf (NBK26821)
    Explains the molecular architecture of DNA, base-pairing rules, and how genetic information is encoded.
  3. RNA Splicing – NCBI Bookshelf (NBK26887)
    Describes how pre-mRNA is processed through intron removal and exon joining, and how splicing errors can impact protein function.
  4. Protein Folding – Nature Education (Scitable)
    Outlines the stages of protein structure formation and the role of chaperones in achieving functional folding.
  5. Post‑Translational Modifications – Biochem J (PMID: 33826699)
    Reviews biochemical modifications such as hydroxylation, glycosylation, and cross-linking that refine protein structure and stability.
  6. From RNA to Protein – NCBI Bookshelf (NBK26829)
    Explains how mRNA codons are interpreted by ribosomes to assemble amino acid chains during translation.
  7. Gene Mutations and Genetic Disorders – MedlinePlus (NIH)
    Introduces different types of genetic mutations and how they can disrupt normal protein production or function.

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Collagen Chaos: How One Protein Explains (Almost) Everything About hEDS