When scientists clone a gene, they isolate and make exact copies of just one of an organism's genes. Cloning a gene usually involves copying the DNA sequence of that gene into a smaller, more easily manipulated piece of DNA, such as a plasmid. This process makes it easier to study the function of the individual gene in the laboratory.
To me a deep thinker is someone who is an innately curious, and deeply insightful. He/she has a profound understanding of the right questions to ask in the face of both reality and the unknown. He/she is not afraid to see reality and what is there before him/her.
Even though it's a very encompassing word, I find it bland to just view people in terms of how deep they are. It's really easy to pin someone as being shallow or deep without understanding what that person is actually thinking. It's very common when it comes to celebrities for people to pin them as shallow or deep before even meeting them. It's more of a label, than a meaningful word IMO. Wouldn't a deep person seek to understand what a person is actually thinking? I would agree it is a label when describing someone you've never met, like a celebrity, but when describing someone you've met, better if several times, I think it is an important and distinguishable quality to note.