The Chrysalids (Unabridged‪)‬

David Strorm's father doesn't approve of Angus Morton's unusually large horses, calling them blasphemies against nature. Little does he realise that his own son, his niece Rosalind and their friends have their own secret aberration that would label them as mutants. But as David and Rosalind grow older it becomes more difficult to conceal their differences from the village elders. Soon they face a choice: wait for eventual discovery or flee to the terrifying and mutable Badland.... 

About the author: John Wyndham Parkes Lucas Benyon Harris was born in 1903, the son of a barrister. He tried a number of careers including farming, law, commercial art and advertising, and started writing short stories, intended for sale, in 1925. From 1930 to 1939 he wrote stories of various kinds under different names, almost exclusively for American publications, while also writing detective novels. During the war he was in the Civil Service and then the Army. In 1946 he went back to writing stories for publication in the USA and decided to try a modified form of science fiction, a form he called 'logical fantasy'.