A 26-year-old author as skilled as Stefan Merrill Block is almost as rare as an American novelist under 40 who has avoided the production line from Ivy League creative-writing course to the publishing industry.

While Block taught himself to write as he worked on this, his debut, the novel is expertly edited, if not rebuilt in parts, and its polish is often similar to that of the prose generated by the best of those courses. But he goes without the thick, evenly applied insulation - made from all the accepted components of critical and commercial success - which often over-protects literary graduates' work from a reader's grubby hands.

Rather than relying on a neat plot hook for impact, Forgetting challenges the assumption that Alzheimer's disease sufferers die horribly. The reader wrestles with the idea that sufferers may be in a blissful state as their memories and cognitive functions are deleted. Any discomfort we feel about that is compounded when Block depicts the carers' torment as they fade from the minds of their loved ones.

Few novelists working today could handle the science behind the disease as well as Block. He has the confidence to create a mutation of Alzheimer's and make it plausible.

He plays with the role of chance in history, taking us back to the big bang, coaching us through the creation of memory - by chance - and the son-father relationship between the two in the development of the universe.

Block's characters, all carrying the strain of Alzheimer's introduced to the world by a duke in Georgian England, reassemble themselves generations later.

By building the detail around his mutation, Block avoids becoming trapped in sentiment, even in a story less involved with Alzheimer's sufferers than their carers, one of whom is a self-absorbed teenaged boy. Block and his characters look for diversions from the tragedy. The teenager, Seth, copes with his mother's illness with exhaustive research to find out why his parents conceived him when they knew about the family's genetic curse. His father retreats into alcohol and all but leaves the house.

This novel becomes more powerful when we learn that the author has a strong chance of developing Alzheimer's. It is improper to admit the influence of the writer's biography in the company of literary types. A novel should stand on its own and The Story of Forgetting is structurally strong. However, in using fiction to explore his personal fears, Block affirms that the novel can go deeper than the more straightforward, and probably lucrative, option of non-fiction misery literature.

Block achieves more than sharing the pain with readers or begging for affection. His novel is a fascinating attempt to converse with Alzheimer's on his own terms, to accept the disease rather than feign a confrontation with it.