Read Online Beyond This Horizon by Robert A. Heinlein - Free Book Online
Authors: Robert A. Heinlein
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produce? Offhand, the question appears simple. An adult male produces hundreds of billions of gametes. Ova are produced on no such wholesale scale, but in quite adequate numbers. It would appear to be a simple matter to determine what combination you want and then wait for it to show up…or at least to wait for a combination near enough to be satisfactory.
But it is necessary to recognize the combination wanted when it shows up. And that can be done only by examining the gene patterns in the chromosomes.
Well? We can keep gametes alive outside the body…and genes, while infinitesimally small, are large enough to be recognized under our ultramicroscopes. Go ahead. Take a look. Is it the gamete we want, or is it one of its lesser brothers? If the latter, then reject it, and look again.
Wait a moment! Genes are such tiny things that to examine one is to disturb it. The radiations used to see a gamete closely enough to tell anything about its chromosomes will produce a storm of mutations. Sorry…the thing you were looking for isn’t there any more. You’ve changed it—more probably killed it.
So we fall back on the most subtle and powerful tool of research…inference. You will remember that a single male gonad cell produces two groups of gametes, complementary in their chromosome patterns. The female producers have the larger heads; the males are more agile. We can separate them.
If, in a given small constellation of male gametes, enough members are examined to determine that they all stem from the same parent cell, then we may examine in minute detail the group producing the sex we do not want. From the chromosome-gene pattern of the group examined we can infer the complementary pattern of the group kept free of the perils of examination.
With female gametes the problem is similar. The ovum need not leave its natural environment in the body of the female. The polar bodies, worthless and non-viable in themselves, are examined. Their patterns are either identical with that of their sister cell, or complementary. Those that are complementary are more numerous than those identical. The pattern of the ovum may be inferred with exactness.
Half the cards are face up. Therefore we know the value of the cards face down. We can bet—or wait for a better hand.
Romantic writers of the first days of genetics dreamed of many fantastic possibilities—test-tube babies, monsters formed by artificial mutation, fatherless babies, babies assembled piece by bit from a hundred different parents. All these horrors are possible, as the geneticists of the Great Khans proved, but we citizens of this Republic have rejected such tampering with our life stream. Infants born with the assistance of the neo-Ortega-Martin gene selection technique are normal babies, stemming from normal germ plasm, born of normal women, in the usual fashion.
They differ in one respect only from their racial predecessors: they are the best babies their parents can produce!
CHAPTER FOUR
Boy Meets Girl
M ONROE-ALPHA called for his ortho-wife again the next evening. She looked up and smiled as he came into her apartment. “Two nights running,” she said. “Clifford, you’ll have me thinking you are courting me.”
“I thought you wanted to go to this party,” he said woodenly.
“I do, my dear. And I appreciate your taking me. Half a minute, while I gown.” She got up and slipped out of the room with a slow-seeming, easy glide. Larsen Hazel had been a popular dancing star in her day, both record and beamcast. She had wisely decided to retire rather than fight it out with younger women. She was now just thirty, two years younger than her spouse.
“All ready,” she announced after an interval hardly longer than her promise mentioned.
He should have commented on her costume; it deserved comment. Not only did it do things with respect to her laudable figure, but its color, a live Mermaid green, harmonized with her hair and with her sandals, her hair
But it is necessary to recognize the combination wanted when it shows up. And that can be done only by examining the gene patterns in the chromosomes.
Well? We can keep gametes alive outside the body…and genes, while infinitesimally small, are large enough to be recognized under our ultramicroscopes. Go ahead. Take a look. Is it the gamete we want, or is it one of its lesser brothers? If the latter, then reject it, and look again.
Wait a moment! Genes are such tiny things that to examine one is to disturb it. The radiations used to see a gamete closely enough to tell anything about its chromosomes will produce a storm of mutations. Sorry…the thing you were looking for isn’t there any more. You’ve changed it—more probably killed it.
So we fall back on the most subtle and powerful tool of research…inference. You will remember that a single male gonad cell produces two groups of gametes, complementary in their chromosome patterns. The female producers have the larger heads; the males are more agile. We can separate them.
If, in a given small constellation of male gametes, enough members are examined to determine that they all stem from the same parent cell, then we may examine in minute detail the group producing the sex we do not want. From the chromosome-gene pattern of the group examined we can infer the complementary pattern of the group kept free of the perils of examination.
With female gametes the problem is similar. The ovum need not leave its natural environment in the body of the female. The polar bodies, worthless and non-viable in themselves, are examined. Their patterns are either identical with that of their sister cell, or complementary. Those that are complementary are more numerous than those identical. The pattern of the ovum may be inferred with exactness.
Half the cards are face up. Therefore we know the value of the cards face down. We can bet—or wait for a better hand.
Romantic writers of the first days of genetics dreamed of many fantastic possibilities—test-tube babies, monsters formed by artificial mutation, fatherless babies, babies assembled piece by bit from a hundred different parents. All these horrors are possible, as the geneticists of the Great Khans proved, but we citizens of this Republic have rejected such tampering with our life stream. Infants born with the assistance of the neo-Ortega-Martin gene selection technique are normal babies, stemming from normal germ plasm, born of normal women, in the usual fashion.
They differ in one respect only from their racial predecessors: they are the best babies their parents can produce!
CHAPTER FOUR
Boy Meets Girl
M ONROE-ALPHA called for his ortho-wife again the next evening. She looked up and smiled as he came into her apartment. “Two nights running,” she said. “Clifford, you’ll have me thinking you are courting me.”
“I thought you wanted to go to this party,” he said woodenly.
“I do, my dear. And I appreciate your taking me. Half a minute, while I gown.” She got up and slipped out of the room with a slow-seeming, easy glide. Larsen Hazel had been a popular dancing star in her day, both record and beamcast. She had wisely decided to retire rather than fight it out with younger women. She was now just thirty, two years younger than her spouse.
“All ready,” she announced after an interval hardly longer than her promise mentioned.
He should have commented on her costume; it deserved comment. Not only did it do things with respect to her laudable figure, but its color, a live Mermaid green, harmonized with her hair and with her sandals, her hair
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