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Chromosome 6 by Robin Cook. Chapter 5, 6

toward Melanie.

‘Come on, Kevin!’ Melanie complained. ‘I didn’t develop the techniques I

use the way you did. There are lots of people who could have done my

job, but only you could have done yours. It was your breakthrough that

was key.’

‘No arguing you two,’ Candace said. ‘Just tell me how it’s done. I’ve

been curious from day one, but everything has been so hush-hush. Kevin’s

explained the science to me, but I still don’t understand the

logistics.’

‘Kevin gets a bone-marrow sample from a client,’ Melanie said. ‘From

that, he isolates a cell preparing to divide so that the chromosomes are

condensed, preferably a stem cell if I’m correct.’

‘It’s pretty rare to find a stem cell,’ Kevin said.

‘Well, then you tell her what you do,’ Melanie said to Kevin, with a

dismissive wave of her hand. ‘I’ll get it all balled up.’

‘I work with a transponase that I discovered almost seven years ago,’

Kevin said. ‘It catalyzes the homologous transposition or crossing over

of the short arms of chromosome six.’

‘What’s the short arm of chromosome six?’ Candace asked.

‘Chromosomes have what’s called a centromere that divides them into two

segments,’ Melanie explained. ‘Chromosome six has particularly unequal

segments. The little ones are called the short arms.’

‘Thank you,’ Candace said.

‘So . . .’ Kevin said, trying to organize his thoughts. ‘What I do is

add my secret transponase to a client’s cell that is preparing to

divide. But I don’t let the crossing-over go to completion. I halt it

with the two short arms detached from their respective chromosomes. Then

I extract them.’

‘Wow!’ Candace remarked. ‘You actually take these tiny, tiny strands out

of the nucleus. How on earth can you do that!’

‘That’s another story,’ Kevin said. ‘Actually I use a monoclonal

antibody system that recognizes the backside of the transponase.’

‘This is getting over my head,’ Candace said.

‘Well, forget how he gets the short arms out,’ Melanie said. ‘Just

accept it.’

‘Okay,’ Candace said. ‘What do you do with these detached short arms?’

Kevin pointed toward Melanie. ‘I wait for her to work her magic.’

‘It’s not magic,’ Melanie said. ‘I’m just a technician. I apply in vitro

fertilization techniques to the bonobos, the same techniques that were

developed to increase the fertility of captive mountain gorillas.

Actually, Kevin and I have to coordinate our efforts because what he

wants is a fertilized egg that has yet to divide. Timing is important.’

‘I want it just ready to divide,’ Kevin said. ‘So it’s Melanie’s

schedule that determines mine. I don’t start my part until she gives me

the green light. When she delivers the zygote, I repeat exactly the same

procedure that I’d just done with the client’s cell. After removing the

bonobo short arms, I inject the client’s short arms into the zygote.

Thanks to the transponase they hook right up exactly where they are

supposed to be.’

‘And that’s it?’ Candace said.

‘Well, no,’ Kevin admitted. ‘Actually I introduce four transponases, not

one. The short arm of chromosome six is the major segment that we’re

transferring, but we also transfer a relatively small part of

chromosomes nine, twelve, and fourteen. These carry the genes for the

ABO blood groups and a few other minor histocompatibility antigens like

CD-31 adhesion molecules. But that gets too complicated. Just think

about chromosome six. It’s the most important part.’

‘That’s because chromosome six contains the genes that make up the major

histocompatibility complex,’ Candace said knowledgeably.

‘Exactly,’ Kevin said. He was impressed and smitten. Not only was

Candace socially adept, she was also smart and informed.

‘Would this protocol work with other animals?’ Candace asked.

‘What kind would you have in mind?’ Kevin asked.

‘Pigs,’ Candace said. ‘I know other centers in the U.S. and England have

been trying to reduce the destructive effect of complement in

transplantation with pig organs by inserting a human gene.’

‘Compared with what we are doing that’s like using leeches,’ Melanie

said. ‘It’s so old-fashioned because it is treating the symptom, not

eliminating its cause.’

‘It’s true,’ Kevin said. ‘In our protocol there is no immunological

reaction to worry about. Histocompatibility-wise we’re offering an

immunological double, especially if I can incorporate a few more of the

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