Donald Moffitt - Genesis 01

had just finished supper, skipping the sweet as usual so that he could plant himself in the common room for the serious business of whiling away the evening. An after-dinner drink was on a small taboret beside him, within easy reach of his hand, and he was reading an old, often-refolded printout of Moliere’s Imaginary Invalid.
    He looked up and brought Bram into focus. “Good halftide, young fellow. Bram, wasn’t it? The bioengineer? Pull up a chair, my boy, and sit down.”
    “Thank you, sir,” Bram said, and settled opposite.
    Doc Pol had grown whiter and more withered since the last time Bram had seen him. His voice was cloudier, his hands less steady. It was impossible to guess how old he might be. He had been a fixture of the lodge when Bram had first met him—fifty years retired and full of dusty, forgotten honors. Some unspecified disappointment had driven him to pare down his life and consign himself to the lodge. Nobody from outside ever came to see him. Perhaps he had simply outlived everyone close to him.
    “You look fit, Bram. Older. Filled out a bit. Let me think. You’d been accepted as an initiate by a Nar touch group. Did you ever get your apprenticeship?”
    “Yes, sir. Thanks to you. The help you gave me with human biology. You know more about molecular repair than anyone I’ve met.”
    “Nonsense,” the old man snorted. But Bram could see that he was pleased. “My practical knowledge was fifty years behind the times. Why, at the time I retired they hadn’t even begun to autoclone cortical tissue. Nowadays it seems that every senescent old fool runs to have it done as soon as he begins forgetting a few things. I wouldn’t do it myself. We have more than enough brain cells to keep us going until we croak—the trick is to keep on using the ones we have left.”
    “Well, cerebral enhancement aside, you certainly opened my eyes about how autoclone grafts work on the cellular level. Kidney tissue, lung tissue, intestinal tissue—even the cellular mechanisms involved in regrowing working structures like limbs.”
    Doc Pol took a small sip of his drink. “Hmph. Clone grafts for injury repair, organ replacement for nonsynchronous wear and tear. That’s about all we bumbling medcrafters are good for, apart from broken bones and obstetrics. Original Man didn’t leave much work for a doctor to do. Not after he edited out the oncogenes and selected for longevity, good eyesight, good teeth, and the rest of it. And kindly kept his germs to himself. It all catches up with you in the end, of course.”
    “That’s what I wanted to talk to you about, sir.”
    “Talk about what?”
    “Why it catches up.”
    Doc Pol turned a pair of bright blue eyes on him. “You mean why can’t we go on recloning parts of our bodies forever and live on as patchworks?”
    “Well … something like that.”
    “Each of us has a fetal analog frozen in nitrogen and put on file before blastocyst implantation. And that’s fine in case of medical catastrophe. Particularly when someone needs a new heart or kidney. But you can go back to the well only so often. And even if that weren’t so, eventually you’d be stitching your patches to worn-out material.” He shook his head sadly. “No, my young friend, if you’re looking for a prescription for immortality, you’ll have to find it in the cell itself. Our fetal analogs stay young only because they’ve been arrested by freezing. Thaw them out, grow the differentiated cells into the replacement part you want—and your new lung or kidney goes through exactly the same number of cell generations as the rest of you. It might outlast you—but not for long.”
    “How many cell generations, Doc? And why does cell division have to stop at all?”
    The old man looked longingly at the backgammon board on his chairside taboret. “About fifty cell generations in human beings. You’d know more about vegetables than I do. As to why they eventually lose the ability to function and replace themselves, there are different theories.”
    Bram leaned forward in an attitude of extreme interest, chin on knuckles, elbows on knees. “Like what?”
    Doc Pol sighed. “One of them is the accumulation of errors. Do you know what collagen is?”
    “A large protein molecule. Chief constituent of connective tissue.”
    “It accounts for about thirty percent of all the protein in the body. It supports the skin, separates the spinal disks, and so forth. Because the molecules are