If this receptor is being degraded, our LDL cholesterol levels will increase (bad news).
"So, how about the complete loss of PCSK9? Turns out that it's not lethal. That's a really important thing. So when drug companies found out that you could actually knock this thing out, and it would be perfectly compatible with life, then that said, this isn't such a risky thing. And a number of companies have made antibodies against PCSK9, and they've been in clinical testing. And here's an example of the effect of a monoclonal antibody to PCSK9 on LDL cholesterol. One injection. That's it, as the antibody then washes out. Decreases quite substantially. Several companies have done this. These haven't yet been approved. I think it's very likely they will be approved. Cool. (...) There are some drugs in clinical testing right now that block that transfer of cholesterol ester from the HDLs (High Density Cholesterol, the good form of cholesterol, that is) to LDLs, and they have a dual effect. They increase HDL and simultaneously lower LDL. They may be very effective, because they're lowering the LDL."
Eric Lander PhD, Geneticist. MITx 7.00x "The Secret of Life", June 2013.