TAGC - to represent any one of these we need to 2 bits.

2 bits x 6 billion / 8 bits per per byte = 1.5 GB

so whole human genome can be stored in 1.5 GB. You have 40 trillion copies of your DNA. that is a lot of redundancy.

less than one part in thousand is unique. so what is unique to you could be stored in less than a mega byte.