What does gattaca say about dna determining a person's potential?

The moral of GATTACA warns against a future where everybody would be judged by their DNA. Instead, a person should be judged on their actions that prove their intentions or the effectiveness. If you remember, the protagonist had difficulty finding the job he wanted because of his hear defect. In spite of his heart defect, he was good at his job, but would have never gotten to work as an astronaut if they could read his DNA. The main character defies the obvious premise in society that genes are the only thing that determines a person's potential.

Ireally dont know sorry