Genetic algorithm usually deals with chromosomes. I have used binary and hexadecimal chromosomes in the past and found that the binary chromosomes are more flexible, especially with bitwise operations.
Let's say a chromosome with four chunks of 4-digit binary, with each digit as dimension of true/false value; we end up with something like 1011 1100 0010 0101. Then I stored these four chunks in four documents in a NoSQL database. Each document then also has the records of other 16-digit chromosomes, so that I can refer to those 16-digit chromosomes contain an exact/similar 4-digit chunk. This was the fastest method I could come up with the last time I worked on it; I am sure that there are more efficient methods out there.
Hopefully, this can shed some light on how the genetic algorithm works.