Weed

by Peter Ponzo

  Chapter 31

  Boone left about 9:30 p.m.. Charlie returned about 10. He looked cadaverous.

  "Well Chuck? How's Pelvis?" I asked.

  "She's quite unhappy, as you might expect. Locked in a cell. She is unaccustomed to being confined."

  "I'll bet she's taking it better than you are. Sit down and I'll make us a drink. I think you need one."

  "Martini," he mumbled, then collapsed into a kitchen chair.

  "Nope," I said. "Not here. We'll sit in the living room. More comfortable. Then we'll talk."

  I held out my hand and he took it. I lead him to a large chair by the fireplace and he just sort of sagged back into it, limp, weak. I walked to a side table and started in on the martinis.

  "Me too, please." Josey was standing at the door. God! She looked awful. Her face was almost shaggy. When she saw me staring, she began to cry.

  "C'mon sweets," I whispered. "Have a seat. Have a drink. I promise I'll get you back to normal. Promise." Charlie didn't even look up.

  For some time we sipped the martinis without talking, then Charlie said, "Miss Fleetsmith, you wanted to talk?"

  "Talk? About what? "

  "You said, recently, that you wanted to talk about some theory—"

  "Mmm, yes. I need to talk to somebody about DNA, regeneration, the weed—and you're it."

  "Can I listen?" Josey asked.

  "Certainly." I leaned back, began to hum then started spilling what had been on my mind for days.

  "Every cell," I began, "for a man or a banana, contains the prescription for making the man ... or the banana. This blueprint is encoded in strings of material called DNA; like beads on a string. The beads on the string are the genes. The string itself is a chromosome."

  If I explained every detail, as though I were giving a lecture, then maybe I could clarify things in my own mind. I continued:

  "This collection of strings, forty-six of them, is buried in the nucleus of each cell ... with one notable exception, which is intriguing. I'll get to that later."

  "Does that mean," Josey mumbled, "that if a man had the beads of a banana then he'd be a banana?"

  "Sort of," I whispered. "But most men are bananas without any genetic assistance. Anyway, the cells continually regenerate. That's normal. Each string of DNA, each chromosome, splits down the middle and produces a matching twin, then the cell divides into two cells, each with a complete set of genes—a replica of the original cell. Now, the effect of Dermafix is just this: when the cell splits, the new cells are not replicas of the original cell. In fact, the genetic information carried in the daughter cells is more ... uh, ancient." I stared at the ceiling. "That's not a good word. Maybe I should explain. You see, much of the genetic information, encoded in the beads on the strings of DNA, the genes, well, it's garbage. There's stuff there that's ... that's ..."

  I started to hum. Just talking about it made me think more clearly. There was something there ...

  "Must be lots of beads," Josey said. "I mean, if the beads tell how to make a man, there's gotta be a lot of beads. I once seen the plans for a machine that Ohshit was going to buy. Pages and pages. When the machine was delivered it was so small, smaller than the plans. But a man—"

  "Dear Miss Cowley," Charles said wearily, "the strings of DNA that I myself possess, if placed end to end, would stretch from here to the moon and back ... several times."

  "Yeah," I said, "and much of it is garbage." I smiled at Charles. "Most of your chromosomes contain genes which have apparently no information whatever. Perhaps it's junk left over from your prehistoric past. A hundred thousand working genes, that's all you've got. The rest is junk. People change. You're different from your father or grandmother. The blueprint changes, mutations occur, the genetic code is modified from generation to generation, parts are left dormant, spare parts perhaps, revitalized by the Dermafix ..."

  I started to hum again.

  "I don't know where I got my beads," Josey groaned, "but they sure as hell ain't the same beads I was born with. Look at me." She raised her arms. They were covered in hair.

  "Yes," I said slowly, "your beads are different than those you were given at birth."

  "Oh lordy," Josey cried, "who gave me these beads? Can I give 'em back?"

  "Dear Miss Cowley," Charles said, exhaustion evident in his voice, "your parents gave you your beads ... and you're stuck with them." Charles turned to me. "Miss Fleetsmith, you said earlier that the genetic material is buried in the nucleus of the cell with some intriguing exception. May we know of that exception?"

  "Mitochondrial DNA," I said. "That's the DNA that lies within the cell, but outside the nucleus, in the cytoplasm which surrounds the nucleus—and that brings us to Josey's question of who gave her her beads." I turned to face Josey. "Your mother's egg and your father's sperm gave you your beads; half from your mother, half from your father. But all of your mitochondrial DNA, outside the nucleus, that's provided by your mother alone. Your father's sperm is a cell with only a nucleus. It's a runt. It has little or no mitochondrial DNA to give. No cytoplasm, hence no cytoplasmic genes."

  Josey was scratching the stubble on her chin, her eyes closed. "Bastard," she muttered. "Never gave me nothin' ... my father ... drank too much, the bastard."

  I turned to speak directly to Charles, but he spoke before I opened my mouth.

  "The women of the Chockli," he said, rising to his feet. His demeanor had changed from weary to enthusiastic.

  "Exactly what I was thinking," I said. "If this thing is genetic and the mitochondrial DNA is only passed down the female line, that could explain what makes the Chokli females different from the males. Not only that, but mitochondrial DNA evolves very rapidly."

  "But Miss Fleetsmith, the males receive mitochondrial DNA. They are, after all, born of the same egg-sperm marriage, receiving this DNA from the mother's egg."

  I was staring again at the ceiling. I was sure there was something there. "They receive their mother's latest version of this DNA," I said slowly. "If any DNA mutations occur within a male he cannot pass these changes to his offspring. But in a female, any modifications to the mitochondrial DNA can be passed to her daughters who can pass it to their daughters ... each can modify it ... pass it on." I looked at Charlie. "If, in the ancient past, the genetic mitochondrial makeup of the female Chokli changed, then that change would be passed only through the female line. If a male has some genetic irregularity in the mitochondrial DNA, and you'd like to know how that irregularity evolved, then you'd better look at his female ancestors, traced back to some African Eve, mother of all men."

  "But, Miss Fleetsmith," Charles insisted, "I repeat: male children also receive the mitochondrial DNA, even though they may not pass it to their offspring."

  "But the big strong males were the hunters, right? They roamed while the women stayed home raising kids and knitting booties. The brave warriors, they wandered off, sowed a few wild oats—"

  "... oats without mitochondrial DNA," Charles added.

  "Exactly! Without mitochondrial DNA," I repeated.

  "But, Miss Fleetsmith," Charles began. I raised my hand and he stopped.

  "You know Charlie," I said slowly, "there's a theory that mitochondrial DNA is not a natural part of our human heritage. Perhaps it originated as the remnants of organisms that invaded the cells of creatures that evolved into man, remaining within the cytoplasm. We have learned to live with it, but it is nevertheless foreign, perhaps one day to reanimate—"

  "But, Miss Fleetsmith," Charles began again.

  "But, Mr. Curran," I responded, not wanting to lose a train of thought, "you say that male offspring inherit mitochondrial DNA. Yet male children are different. They are male simply because they have X and Y chromosomes. Female offspring have no Y chromosome, but they do have two X chomosomes. That means ... that means ..." I started again to hum. I didn't quite know where this was leading, but being able to speak my thoughts aloud was clearly h
elping.

  "Yes, Miss Fleetsmith?" Charles asked, encouragingly.

  "Mmm ... two X chromosomes, two big X chromosomes, not your pygmy Y. Each X containing genetic information, similar genetic information, two copies of each gene, yet only one of the two X chromosomes is active—the other is switched off."

  "Switched off?" Charles was sitting on the edge of his seat. It wasn't clear whether he was really interested or just being sympathetic to my ruminations.

  "Yes, switched off, dormant. Can't have conflicting instructions on how to make a woman, so one set of genes is switched off."

  I smiled directly at Charles. "Women have more genetic information than men," I said. "Does that surprise you?"

  Charles didn't answer, so I continued. "Lyonisation. Only one of each pair of genes on the X chromosomes is utilized. The other is inactive. Like the garbage DNA, inactive yet somehow revitalized by Dermafix."

  "Miss Fleetsmith?" Charles said. "Lionization? As in King of the Jungle?"

  "Has nothing to do with that lazy male feline. Mary Lyon, a geneticist. She discovered this feminine aptitude for turning off the genes in one of the X chromosomes. It's called Lyonisation."

  "Quite remarkable."

  "Yes, but not unusual. In fact, there are always working genes and dormant genes. The forty-six chromosomes in each body cell? Twenty-two pairs, with matching genes in each pair, from Mom and Dad, only one of the matching genes working. Maybe you get Mom's hair color, Pop's nose. For example, the working genes in bone marrow are the ... uh, uh, it's been a long time since I took that course in molecular genetics."

  "Twenty-two chromosome pairs doesn't quite make forty-six," Charles said.

  "Mmm ... sex."

  "Beg pardon?"

  "Twenty-two chromosome pairs plus the two sex chromosomes, X and Y, in men only— the pair don't match. Any gene on the X you got from your mother, guaranteed. Bad habits attached to the Y you definitely got from Pops. Women have a choice. Two X's. Maybe Mom's gene is working, maybe Pop's."

  I was thinking. Charles was silent for a moment, then he said, "Perhaps Dermafix switches genes on and off. Perhaps the dormant genes are activated. Perhaps—"

  "Beta-globin."

  "Beg pardon?"

  "Beta-globin. I did remember. That was one boring course, but now I remember. The working genes, producing red blood cells in the bone marrow ... I think. The rest of the DNA in bone marrow cells are switched off."

  I really should have paid more attention in class. I hummed a bit, stared at the ceiling, couldn't think of anything else to say. My mind was a blank.

  "Charlie," I said finally, "why so few females among the Chokli?"

  He shrugged. I looked at Josey. She was sleeping. I didn't blame her.