I'm by no means an expert on the subject, but my understanding is that the process of "multiplying" a specific DNA sequence (known as PCR, or polymerase chain reaction) is patented, with the proviso that universities can use it for free, but corporations maing profit need to pay? This seems like a good system to me - it allows work to be done, but also means the company can make a bit of money, which (ideally) would be pumped back into research.
I just quickly reread a section in that book - I got a few wires crossed. The gene I was talking about is known as "CCR5", and is patented by a company known as HGS (Human Genome Sciences). It was identified about a year after the patent was imposed that mutations in CCR5 could either increase or decrease a cells resistance to infection by HIV. The patent covers any research on the gene, with the intent to use the research in manufacturing a drug. That kinda puts a damper on AIDS research...
Cheers,
Brad