(edits in marrow, edits in mind)
On VDJ Recombination, Human Memory, and the Art of Adaptation
Woodland is living up to everything I hoped it would be. The deck is done—fresh pine under my feet, the night air thick with the sound of tree frogs. It’s the kind of night where the world’s noise fades far enough away that you can finally hear yourself think. And tonight, my thoughts go to one of the most astonishing pieces of biology I have ever learned: VDJ recombination.
If there was ever a process that convinced me biology could be both wild and exquisitely precise, this was it. Back at Illinois, the late Professor Roderick MacLeod’s lectures on immunology were a kind of initiation. His thick Scottish accent carried an authority that made even the most abstract molecular diagrams feel solid. And in Janeway’s Immunobiology, those diagrams weren’t just illustrations; they were blueprints—maps of a hidden order I could study until it felt almost knowable.
VDJ recombination begins with a break. RAG1 and RAG2 (recombination-activating genes) recognize tiny recombination signal sequences flanking the variable (V), diversity (D), and joining (J) gene segments. They cut, cleanly. Terminal deoxynucleotidyl transferase (TdT) then steps in, scattering random nucleotides into the gap, creating raw molecular noise. DNA repair enzymes stitch it all together, and from that chaos emerges a single exon, a unique genetic key encoding the antigen-binding site of an antibody. One cell. One rearrangement. One entirely new possibility.
When Susumu Tonegawa uncovered this process in the 1970s, it was like opening a trapdoor under everything we thought we knew. The immune system was not fixed. It rewrote itself, over and over, until it built a library of molecular solutions vast enough to defend the body against almost anything it might one day encounter. It was reckless and methodical at once—a biological gamble that somehow always pays off.
Out here at Woodland, I keep thinking about that gamble. This summer has become a kind of mid-career sabbatical, a season for building—not just this deck, but the life that will grow from it: the cabin, the woodshop, the metal shop, the maker’s space where I’ll work on art and science and whatever else I can bend into existence. A microscope will sit here soon. A telescope. Maybe even a radio antenna. This place is a blueprint of its own, an unfinished diagram I get to fill in.
And as I’ve been sketching and re-sketching my plans for the cabin, I’ve realized something: every new drawing is its own rearrangement. The first draft never fits. A wall moves. A window shifts. A workbench stretches out another foot. Planning isn’t about getting it right the first time—it’s about recombining the pieces until something clicks, until the form matches the function you didn’t even know you needed.
Which brings me back to VDJ. I’ve started to wonder if this is what we’re all doing in our own lives: reshuffling, testing, and refining until the shapes we’ve made finally match the challenges in front of us. Maybe this isn’t just a biological trick. Maybe it’s a philosophy.
Even autoantibodies fit this metaphor. We tend to think of them only as destructive, but many serve subtle regulatory roles, keeping the immune system in balance. I can’t help but see in them a form of molecular introspection—a way of testing the self against the self, of making tiny, necessary adjustments. Maybe our experiences do the same thing: a kind of adaptive self-reflection, building resilience in the only language that matters—trial, error, and change.
When I first learned VDJ recombination in MacLeod’s lectures, I loved it because it felt like an answer. Now I love it because it has become a question. How else might we live, if we trusted in our capacity to rearrange?
Memory feels like its own kind of recombination. Every challenge, every joy, every small night like this splices into us. Out here, even the act of moving my cabin door on paper for the fifth time—trying to see how the light would fall—feels like part of a larger sequence assembling itself. It’s not failure; it’s an immune response to possibility.
This is what adaptation really is. Antibodies diversify with every new exposure. So do we. We’re not designed to be fixed. We’re designed to meet the unknown and make something out of it.
That’s why Woodland matters. It’s not just a place for escape; it’s an immune organ of my own making, a quiet factory for what comes next. Every project here—every beam, every shifted doorway, every late-night stretch of thought—is a rearrangement, a way of stockpiling the raw material for whatever I will need to face.
Above me, stars burn holes through the dark, unblinking. The frogs keep their restless chorus. And I think of my B cells, working in silence, rewriting their codes in an endless rehearsal for survival. In them, I see the shape of my own task: to keep revising, to keep adapting, to trust that I am not finished. I am an unfinished repertoire, and that is exactly what I am meant to be.