Imagine if the world want to have a universal ID code ... how should you go about making one. My personal approach would be to convert our DNA sequence into some sort of a code. There are 'A' , 'C' , 'G' , 'T' for the DNA sequence. These four letters can be used as it is to generate the code or it maybe represented by certain bits or bytes. When the full DNA has been converted into a list of ACGT or bytes or bits , some hash functions can be used to make the code more efficient. DNA is unique in everyone so if you want a convenient universal ID , a DNA saliva swap , encoding and hashing can be applied (the hashing and encoding should have only one style for ease) and you would get the person's universal ID.
I wouldn't encourage universal ID because it's going to hinder personal privacy and as you know , data leaks by hacking and bad softwares or espionage is so common... no data can be gauranteed safety and privacy ... and who knows what people might do to you with your ID known to them... I think universal ID is not a good idea .
This is an abstract thought on how to implement ... but I would discourage anyone trying to use my method above to use it for universal ID.
Disclaimer: If this method is somehow available before the date of publishing of this post, by no ways or means do I know anything. This is a thought that came to my mind rather than referencing someone's ideas.