The Chromosome Game by the late British author Christopher Hodder-Williams (
ISFDB,
Wikipedia,
obituary at The Independent) is his science fiction technothriller unusually taking place in a future dystopian world (rather than the almost-contemporary Britain he usually used), where it appears the remains of humanity exist in an alternate dimension outside a barren wasteland, and a group of adventurous persons is tasked to investigate and locate the remains of a long-ago genetic engineering experiment that may revitalize the human race, free for a limited time courtesy of publisher Endeavour Press' Venture imprint.
This was originally published in 1984 by Mithras Publishing Limited, and appears to have been the final novel that was published before he retired due to illness and passed away (his obit says he completed another one shortly before he died, which hopefully Venture will publish posthumously for his fans

).
Currently free @
Amazon (available to Canadians & in the UK and pretty much everywhere else Amazon sells worldwide, since this is being done via their KDP Select exclusive-or-else program)
Description
THE STAKES ARE HIGH FOR THE PLAYERS OF THE CHROMOSOME GAME
THE PRIZE: THE SURVIVAL OF THEIR SPECIES.
This is Futureworld, which twentieth century scientists had planned for so desperately in horrifying circumstances.
On the outside is a ruined landscape where nature has both suffered and evolved. The world has become a barren wasteland.
Has the history of mankind been erased forever? Or has earth been abandoned?
Whilst others look on, the terrifying aftermath of mortal life in an alternate dimension plays out and a universal order comes to light…
Meanwhile, a preserved vision lies in wait. Carefully selected human DNA conserved in gene banks is the only legacy of a disturbing and volatile experiment.
This may be the only chance they have left – but can anything be reconstructed or salvaged?
Trell, Kelda, Eagle and Krand form part of a chosen group to investigate. The stakes have never been higher, and the clock is ticking towards the final doom of the human race…
The Chromosome Game is another gripping techno thriller from Christopher Hodder-Williams, set in the eerie void of the Futureworld – a dark, dystopian vision of the world as it may soon become.