Return of the Convict — William Alan Thomas

It's March 9, 2143. In the aftermath of wars, plagues and environmental breakdown, there's growing hope. Humans have colonized the solar system and now they're looking to the stars.
Thanks to extensive brain implants, space cadet Dom Tessier enjoys a perfect memory. In another year he's to be fully transformed, and join the world-wide technocracy. He and his girlfriend Astra Allison practice telepathy together, and attain new heights.
Unbeknownst to Dom, his upbringing and education have been provided for by his parent clone, Lucas Rivera, a diseased convict who's now returned from Martian exile.
Dom's brain implants offer Lucas the chance for a life-saving mind merger, and he intends to make that happen.
Meeting Lucas is a real shock for Dom. Lucas is uncultured, and no stranger to vice. Worst of all, he's a convicted criminal. Can Dom overcome his prejudices, and embrace the one who's given him everything? Or will he coldly let Lucas die? If you like hard sci-fi you'll love this book.