THE genome vs. MY genome

As said in a previous post, the human genome has been sequenced in 2001. Remember the genome is the sequence of nucleotide defining most physical characteristics of an individual. Since then, everyone is talking about “the” human genome. Now a little riddle:

If there is one human genome, how come personal genomics companies now offer to analyze your personal genome?

Is it swindle? Do they sell every time the same information? Of course they don’t. And if you subscribed to their services, you probably paid for valuable information.

In fact the human genome must be seen rather as a map indicating the probabilities of seeing each nucleotide (A, C, G and T) at each location of the genome of an individual. So for example, at a given place in your genome, the nucleotide “A” may be observed. However, maybe at this place the expected nucleotide is “G” in 95% of human beings. This may reveal a specific trait of your genome. 

This is related to SNPs (Single Nucleotide Polymorphism) which surely will be covered in another post. Keep reading!