‘And now?’
‘Now I believe that the changes were done by another faction entirely. Shall I spell it out?’
‘Please do.’
‘The work bears certain signatures which suggest that the sequences were inserted using the genetics techniques common to Ultras. Neither more nor less advanced than bloodcutter or Mixmaster work — just different, and highly individual. I should have realised much sooner.’ He allowed himself a smile, obviously impressed by his own deductive skills. ‘When Mixmasters perform a genetic service, it’s essentially permanent, unless the client specifies otherwise. That doesn’t mean that the work isn’t reversible, in most cases — it just means that the genetic and physiological changes will be stable against reversion to the older form. Bloodcutter work is the same, for the simple reason that bloodcutter sequences are generally bootlegged from Mixmasters, and the ’cutters haven’t the ingenuity to embed obsolescence into those same sequences. They steal code, but they don’t hack it. But Ultranauts do things rather differently.’ The Mixmaster cradled his long and elegant fingers before his chin. ‘Ultras sell their services with an in-built obsolescence; a mutational clock if you will. I’ll spare you the details; suffice to say that, within the viral and enzymic machinery which mediates the expression of the new genes inserted into your own DNA, there is a time-keeping mechanism, a clock which functions by counting the accumulation of randomness in a strand of foreign reference DNA. Needless to say, once these errors exceed a pre-defined limit, cellular machinery is unshackled which suppresses or corrects the altered genes.’ Again the Mixmaster smiled. ‘Of course, I’m simplifying tremendously. For a start, the clocks are set to trigger gradually, so that production of the new proteins and the division of cells into new types doesn’t cease suddenly. Otherwise it could be fatal — especially if the changes allowed you to live in an otherwise hostile environment, like oxygenated water or an ammonia atmosphere.’
‘You’re saying Tanner’s eyes were touched by Ultras?’
‘You catch on extraordinarily swiftly. But there’s rather more to it than that.’
‘There generally is,’ I said.
The Mixmaster danced his hands over the console, fingers plucking at invisible harp strings, causing reams of genetics data to spring into the air, particular sequences of Ts and As and Gs and Cs highlighted and cross-linked to a series of physiological and functional maps of the human eye and the associated brain regions of visual comprehension. He looked like a wizard suddenly accompanied by ghostly — and gory — familiars.
‘Something very odd has happened here,’ the man said, his fingers ceasing their too-dexterous dance. He sketched a particular block of base-pairs, the cross-linking rungs of DNA. ‘These are the pairs which are allowed to grow progressively more random; the internal clock.’ His finger moved to another highlighted block which looked superficially identical. ‘And this is the reference map, the unmutated DNA. It’s by comparing these — by noting the number of mutational changes — that the clock is driven.’
‘There don’t seem to be very many changes,’ Zebra said.
‘A few statistically minor point deletions or frame shifts,’ the Mixmaster said. ‘But nothing significant.’
‘Meaning what?’ I asked.
‘Meaning that the clock has not had very long to run. The two sets of DNA have hardly begun to diverge.’ His eyes narrowed. ‘That means that the work was done very recently; definitely within the last year, and perhaps only a few months ago.’
‘Why is that a problem?’ Zebra asked.
‘Because of this.’ Now his finger moved across a densely tangled blob, rendered in lilac. ‘This is a transcription factor; a protein that regulates the expression of a particular set of genes. It is not, however, a normally occurring human protein. Its only function — and it has been engineered for this purpose — is to suppress the newly inserted genes in your eye. It should not be present in large quantities until the mutational clock has been triggered. Yet I found it in abundance.’
‘Could the Ultras have deceived Tanner?’
The Mixmaster shook his head. ‘Not likely. There’d be no economic gain in doing so. The genetics changes would still have been made, so it’s not as if it would be cheaper for them to reset the clock. In fact it would harm their longterm profits, because Tanner — if that’s your name — would have sought the services of another crew.’
‘I take it you have an alternative explanation?’
‘I do, but you may not like it.’ Once again he delivered a smile of utter salaciousness. ‘It would be exceedingly difficult to reset the mutational clock to zero without triggering all sorts of secondary anti-tamper safeguards. Even for a Mixmaster. I could do it, but it would be far from trivial work. But the opposite procedure would be considerably simpler.’
‘The opposite procedure?’ I leaned forward, feeling that some kind of fundamental revelation was almost within my grasp. It wasn’t a feeling I much enjoyed.
‘Setting the clock forward, so that the new genes are switched off.’ He said that, and then allowed himself a moment’s contemplative silence, spinning the projected eyeball with the tip of one finger, a singularly macabre globe. ‘It would be simpler because there would be no safeguards. It would never occur to the Ultras to protect against that kind of tampering, because it would only harm the client. Which is not to say it would be easy. It would, however, be an order of magnitude easier than setting the clock back. It could be attempted by any bloodcutter who understood the problem.’
‘Go on.’
His voice took on a gravitas it had lacked a moment earlier, as if he had triggered his own mutational change to deepen the response of his larynx. ‘For some reason, someone set your clock forward, Tanner.’
Zebra looked at me.
‘You mean Tanner’s changes are fading?’ she asked. I realised that she still had no idea what form these changes took.
‘That was probably the intention,’ the Mixmaster said. ‘Whoever did it was not entirely lacking in competence. Once the clock had been wound, the cells in your eye would have begun manufacturing normal human proteins, cell division following the normal blueprint.’ He sighed. ‘But whoever did it was either sloppy or hasty or both. They reset only a fraction of the clocks, and then imperfectly. There’s a small war going on in your eye, between different components of the Ultra genetics machinery. Whoever tried to reset the clock thought they were turning the machine off, but all they really did was throw a spanner in its works.’ A note of sorrow entered his voice. ‘Such haste. Such dreadful haste. Of course, whoever it was more than deserved to fail. The question is why they thought it was worth doing in the first place.’ His eyes opened in expectation, and I realised he thought I was going to give him an answer.
But I saw no sense in giving him that pleasure, much as I would have liked to. Instead I said, ‘I want a scan. A full-body scan. You can do that, can’t you?’
‘It depends what you want it for; the kind of resolution you want me to achieve.’
‘Nothing too fine. I just want you to look for something. Tissue damage. Internal. Wounds which may or may not have healed.’
‘I can but try,’ the man said, gesturing to the couch, a skatelike scanning device already gliding down from the ceiling.
It did not take very long. In all honesty, I would have been surprised if the Mixmaster scan had revealed anything other than what I was dreading and expecting. It was just a question of seeing it revealed in the cold indices of a readout; just a question of finally burying any residual traces of denial — and, for that matter, hope, which might have remained.