“All right,” said Ponter.
“In fact—Mega here is your daughter, right?”
“Yes, I am!” said Mega.
Vissan crouched down to be at Mega’s face height. “Now, she has brown eyes, whereas you have golden ones,” said Vissan. “Do you have any other children?”
“An older daughter, named Jasmel.”
“And what color are Jasmel’s eyes?”
“The same as mine.”
“She’s so lucky!” said Mega, pouting.
“Indeed she is,” said Vissan, rising and patting the girl on her head. She looked at Ponter. “Brown is dominant; golden is recessive. The chances of a child of yours inheriting your eye color through natural processes were one in four. But if you’d let the codon writer output your genetic material for you, you could have chosen to give both your children golden eyes—or any other trait you or your woman-mate carried the genetic code for.”
“Aww,” said Mega. “I wish I had golden eyes!”
“Understand?” said Vissan. “What happens in a natural conception is that a set of traits selected entirely at random ends up being combined together.”
Ponter nodded.
“But don’t you see?” said Vissan. “That’s a crazy way to do it! An absolute gamble as to what you are going to get. And it doesn’t have to be related to things as inconsequential as eye color. You possess two genes related to the flexibility of the lens in your eye: one from your mother, and one from your father. Say the one you got from your mother is a good one that lets you see without corrective eyewear well into old age, but the one you got from your father is a bad one that would require you to use corrective eyewear from childhood. You will pass one, and only one, of those two on to your own offspring. Which would you choose?”
“My mother’s one, of course,” said Ponter.
“Exactly! But, in natural conception, there is no choice—no choice at all. It’s pure luck of the draw which one your child will get…because you let inefficient nature produce your sperm. But if we sequenced your deoxyribonucleic acid, we could choose the better one of each pair of traits you yourself had inherited, and then we could manufacture a haploid set of chromosomes containing only those better traits. We could also do the same thing with Mary, here, producing a haploid set representing only the better traits from her repertoire. And then we could combine them together to produce the best child you could possibly have. The child would still absolutely be one-half its father genetically and one-half its mother, but it would have the best possible combination of their respective genetic material.”
“Wow,” said Mary, shaking her head. “It’s not quite designer babies, but…”
Vissan shook her head. “No, although that’s technically possible with the codon writer, too: we could code in alleles that are present in neither parent. But that was never my intention. Generation 149 is to be conceived shortly—and I wanted it to be the greatest generation ever, bringing forth all the positive characteristics of the people who begat it, but none of the negative ones.” She shook her head again, and her tone grew even lower than normal. “It could have done as much to improve our species as the purging of the gene pool did.” After a moment, though, she seemed able to push her bitterness aside, at least temporarily. “That will never be, apparently. But at least the two of you can benefit from this capability.”
Mary felt as though her heart were going to burst. She was going to be a mother! It was really going to happen. “This is fabulous , Vissan. Thank you! Can you show us how it works?”
“Certainly,” she said. “I hope its batteries are still charged…” She touched a control, and a moment later a square screen came to life in the center of the unit. “Of course, you can attach a bigger display. Anyway, you pour appropriate raw chemicals into this aperture here.” She pointed to a hole on the right side of the unit. “And the output comes out here, suspended in pure water.” She indicated a spigot at the left end. “Obviously, you’ll want to hook it up to appropriate sterilized glassware.”
“And how do you specify the output?” asked Mary, staring at the machine in fascination.
“One way is by voice,” said Vissan. She pulled out a control bud and addressed the device. “Produce a string of deoxyribonucleic acid 100,000 nucleotides long, consisting of the codon adenine-cytosine-thymine over and over again.” She looked at Mary. “That’s the code for the amino acid—”
“For threonine,” said Mary.
Vissan nodded. “Exactly.”
Several green lights appeared on the device. “Ah, there—it’s saying it needs to be fed raw materials.” She pointed to the screen. “See? They’re specified here. Anyway, you can also use one of several keypads to input data.” She pointed at a toggle switch. “You select either deoxyribonucleic-acid or ribonucleic-acid mode here. And then you can input data at any level of resolution, right down to individual nucleotides.” She indicated a square arrangement of four buttons.
Mary nodded. The toggle must have been set for DNA mode, since the buttons were displaying the Neanderthal glyphs for adenine, guanine, thymine, and cytosine. She pointed to another cluster of buttons, arranged in an eight-by-eight grid. “And these must be for specifying codons, right?” Codons were the words of the genetic language, and there were sixty-four of them, each consisting of three nucleotides. Each codon specified one of the twenty amino acids that are used to make proteins. Since there were more codons than there were amino acids, multiple codons meant the same thing—genetic synonyms.
“Yes, that’s right,” said Vissan. “Those buttons let you choose codons. Or, if you do not care which codon is used to specify a given amino acid, you can just select the amino acid by name here.” She pointed at a cluster of twenty buttons, arrayed in four lines of five.
“Of course,” continued Vissan, “these controls are normally only used for fine editing; it would be incredibly tedious to specify a lengthy deoxyribonucleic-acid sequence by hand. Normally, one interfaces this device to a computer and simply downloads the genetic design one wishes to manufacture.”
“Amazing,” said Mary. “You wouldn’t believe the gyrations we go through to do gene splicing.” She looked at Vissan. “Thank you.”
“My pleasure,” said Vissan. “Now, let’s get down to work.”
“Now?” said Mary.
“Of course. We won’t produce the actual DNA, but we’ll get the process set up. First, we’ll take samples of your deoxyribonucleic acid and Ponter’s, and then sequence them.”
“You can do that here?”
“The codon writer can. We just feed in a sample of deoxyribonucleic acid, and let it analyze it. It should take about a daytenth for each specimen.”
“Only a daytenth to sequence an entire personal genome?” said Mary, astonished.
“Yes,” said Vissan. “Let’s get it started, and then I’ll go catch us something to eat.”
“I’d be glad to help in the hunt,” said Ponter. He smiled and raised a hand. “Although I know you don’t need it.”
“I would welcome the company,” said Vissan. “But first, let’s collect some genetic material from each of you…”
Chapter Twenty-four
“ If the dangers posed by the collapsing of this Earth’s magnetic field teaches us anything, it is that humanity is too precious to have but a single home—that keeping all our eggs in one basket is folly…”
Ponter called the travel-cube driver and told him to head back to Kraldak; they would summon another cube later in the day to take them home.
Mary and Mega stayed back in the cabin, while Vissan and Ponter went off hunting. Mega showed Mary how her new toy worked; Mary paraphrased part of Kipling’s The Jungle Book for Mega; and Mega taught Mary to sing a short Neanderthal song. It was a kick spending time with Mega—and Mary knew it would be even more wonderful to have a child of her own.
Finally, Vissan and Ponter returned with a pheasant they’d caught for dinner, which Vissan proceed
ed to cook while Ponter made a salad. It turned out there were solar panels on the roof of Vissan’s cabin, and she had a vacuum box for storing food, an electric heater, some luciferin lamps, and more; friends had given her farewell gifts when she’d chosen to leave structured Neanderthal society. All in all, Mary thought it actually might not be that bad a life, as long as one had plenty to read. Vissan showed Mary her datapad, and how she could recharge it from the solar array on the cabin’s roof. “I have some four billion words of text stored on this,” she said. “My access to new works has been cut off, of course—but that’s all right; the new stuff is all garbage, anyway. But the classics!” Vissan hugged the little device to her chest. “How I love reading the classics!”
Mary smiled. Vissan sounded just like Colm, extolling the virtues of Shakespeare and his contemporaries; she’d had to keep her Harlequin romances out of his sight, lest an argument ensue.
The dinner was delicious, Mary had to admit—or maybe, she reflected, she was just famished after all the hiking she’d done that day.
The codon writer had been moved to the floor during dinner, but once they’d finished eating, Vissan lifted it back up onto the table. Mega curled up in a corner and had a nap, while the three adults sat around the table: Vissan on the one chair, Ponter on the end of a log, and Mary, facing the cyclopean mammoth skull, perched atop the vacuum box.
“All right,” said Vissan, peering at the display. “It’s finished sequencing.” Mary was looking at Vissan, rather than the square screen, since, with a few exceptions that she’d picked up along the way, she couldn’t understand the glyphs it was showing. But Vissan was oblivious to that, and pointed at the screen. “As you can see, it’s made a list of the 50,000 active genes in your deoxyribonucleic acid, Mare, and the 50,000 in Ponter’s.”
“Fifty thousand?” said Mary. “I thought there were only 35,000 active genes in human DNA. That’s our latest count.”
Vissan frowned. “Ah, well, you’re missing out on…I’m not sure what you call it. A kind of exonic redoubling. I can show you later how that works.”
“Please,” said Mary, fascinated.
“In any event, the device has now made a list of 50,000 gene alleles you each possess. That means the codon writer could now just go ahead and produce what you need: a pair of gametes that have the same number of chromosomes. But…”
“Yes?” said Mary.
“Well, I told you the original intention of this device: to let parents pick and choose from the alleles they could offer a child.”
“I think we’ll be happy to just try our luck randomly.” The words were out before Mary really had time to think about them; perhaps, she realized, it was some of her natural Catholic revulsion at tinkering with the stuff of life coming to the surface…although any use of this machine certainly qualified as major tinkering!
Vissan frowned. “If you were both Barasts, I would be content to accept that answer—but then again, as you yourself observed, Mare, if you were both Barast, you wouldn’t need the codon writer just to randomly combine your genetic material.” She shook her head. “But you are not both Barasts.” She looked down at Ponter’s forearm. “I never thought I’d use one of these again, but…Companion of Ponter!”
“Healthy day,” said a male voice from the device’s external speaker. “My name is Hak.”
“Hak, then,” said Vissan. “Surely studies have been done of the differences between Barasts and Gliksin deoxyribonucleic acid since contact was made with Mare’s people?”
“Oh, yes,” said Hak. “It has been quite the hot topic.”
“Are those studies available through the planetary information network?”
“Of course.”
“Good,” said Vissan. “We will need to access them as we go along.” She looked up and shifted her gaze from Mary to Ponter, then back to Mary again. “I strongly advise against just slapping your deoxyribonucleic acid together. We are talking about combining two species here. Now, yes”—she gestured at the codon writer’s screen—“it’s clear that the genomes for Barasts and Gliksins are almost identical, but we should really examine where they diverge, and carefully select combinations.” She pointed at Mary. “Are tiny noses like that typical of your species?”
Mary nodded.
“Well, there, you see? It would be ridiculous to code for a tiny Gliksin nose and a giant Barast olfactory bulb. Traits should be chosen with care so that they enhance, or at least do not interfere with, each other.”
Mary nodded. “Right. Of course.” Butterflies were pirouetting in her stomach, but she tried to sound jaunty. “So, what’s on the menu?”
“Hak?” said Vissan.
“The genetic divergence—”
“Wait!” said Vissan. “I haven’t asked you a question yet.”
Ponter smiled. “Hak is a very intelligent Companion,” he said. “Do you know Kobast Ganst?”
“The artificial-intelligence researcher?” said Vissan. “I know of him.”
“Well,” said Ponter, “about ten months ago, he upgraded my Companion. You weren’t the only one trying to improve the lot of Barasts, of course. Kobast wants everyone in generation 149 to have the benefit of truly intelligent Companions.”
“Well, let’s hope they don’t shut Ganst’s work down as well—although if they do, I’ll be happy to have a neighbor. In any event, I was about to ask Hak to summarize what is known about how the Gliksin genome differs from the Barast one.”
“And I was about to tell you,” said Hak, sounding slightly miffed. “There are, as you observed, about 50,000 active genes in any Gliksin or Barast. But 98.7% of those have allele forms that exist in both populations; only 462 genes have forms that exist in Barasts but not in Gliksin, or vice versa.”
“Fine,” said Vissan. She looked at Mary. “You can leave the rest to chance, if you like, but I really think we should carefully look at those 462 genes, and make sensible choices for each of them.”
Mary looked at Ponter, to see if he had any objection. “That’s fine,” she said.
“All right—although, before we start, there are two big questions we must resolve. With the codon writer, we will make a diploid set of chromosomes combining deoxyribonucleic acid from both of you. Do we make twenty-three pairs of chromosomes, or twenty-four? That is, at the level of the chromosome count, do you want your child to be a Barast or a Gliksin?”
“Wow,” said Mary. “That’s a good question. The work I did in my world was about defining which species a person belongs to for immigration purposes. It seems likely that chromosome count will be adopted as the legal standard.”
“Your child can be a hybrid in many ways,” said Vissan. “But in this, it must be one or the other.”
“Um, gee…Ponter?”
“You are the geneticist, Mare. I rather suspect that matters of chromosome count are—how would you put it?—‘nearer and dearer to your heart’ than they are to mine.”
“You don’t have a preference?”
“Not on an emotional level, no. I suspect, though, that there are legal advantages to making our child genetically Gliksin.”
“How so?”
“We have a unified world government—the High Gray Council. You have 191 member states in your United Nations, plus some more besides that are not members, and immigration issues will arise with each of them, no?”
Mary nodded.
“It seems easier to convince one world government that a being with twenty-three pairs of chromosomes should be able to live and work anywhere in my world than it will be to convince some 200 governments in your world that a being with twenty-four pairs of chromosomes should be accorded the same rights.”
Mary looked at Vissan. “We’re not actually going to manufacture the DNA for our child today, right?”
“No, no, of course not. That will be done back in your world, I presume, when you are ready to become pregnant. I am just taking you through the issues you must deal with.”
??
?So we don’t have to decide right now.”
“That is correct.”
“Well, then, let’s table that one.”
Vissan looked at the table in front of her. “Pardon?”
“I mean, let’s set it aside for now. What’s next?”
“Well, this has nothing to do with your special circumstances but must also be decided, since it affects how the codon writer apportions Ponter’s deoxyribonucleic acid. Do you want a boy or a girl?”
“We’ve already discussed that,” said Mary. “We’re going to have a daughter.”
Vissan touched a control on the codon writer. “A girl it is,” she said. “Now, let’s see what else we’ve got…” She looked at the display.
“The next gene sequence displayed,” said Hak, “refers to hair part. Barasts have a natural part along the centerline of the scalp, right above the sagittal suture. Gliksins tend to have natural parts off to the sides. Mary seems to have alleles only for side parts; both alleles from Ponter’s personal genome are, of course, for center parts. You could take one of each, and discover experimentally which is dominant, or you could take both of Ponter’s and neither of Mare’s, or both of Mare’s and neither of Ponter’s, and be reasonably sure of the outcome.”
Mary looked at Ponter. The Neanderthals did indeed part their hair like bonobo chimpanzees. At first she’d found it quite startling, but she’d since gotten used to it. “I don’t know.”
“The side,” said Ponter. “If she is going to be a girl, she should take after her mother.”
“Are you sure?” asked Mary.
“Of course.”
“The side then,” said Mary. “Use both of my alleles.”
“Done,” said Vissan, touching some more controls. She indicated the square display. “You see how it’s done? These touch-points on the screen select alleles?”
Mary nodded. “Quite straightforward.”
“Thank you,” said Vissan. “I worked hard to make it easy to use. Now, I recognize the next group of alleles, at least on Ponter’s side: they are for eye color. Mare, your eyes are blue—something we never see here. Ponter’s are a golden brown shade we call delint ; it is uncommon, but prized all the more because of that.”