I think of course he had it in his genetic potential. However the utter drive and dedication with insanely high intensity and heavy duty grueling workouts. combine all that with all the different items in the arsenal.

The work on all sides has to be put in. Those who work harder will always surpass those that do not.
Look at Ronnie just before he shot to the top , he was what running #12 ?
)add aceto,expert in all facets medical+chemical+ dietary , then higher intensity training and pain endurance beyond comparison.

Not to say He, RC or Ramy or others may not have been or are not currently manipulating myostatin, using IL-15 or using gene manipulation technologies, but you better believe they have the ability to endure pain beyond what most can imagine. RC, DY and Jay anyway, I have not seen much of Ramy's training. In deed it does not register to them as pain, not in the same way it does most people or most bodybuilders.
-someone can have the nearly the same genetics, same diet & protocols, at that point it is drive, work , ability to press beyond what most stop at (DY, RC Jay all most all of them their workouts would decimate most other pros much less anyone else)

So definitely genetics play a huge role for this or whatever particular sport, so do all the tools or items available, but the nose to the grind stone iron will , dedication and hard work and willingness to ho harder longer can not be left out of the equation.

You take a genetic beast with less drive on a ton of gear and put him up against a guy with say 80% of the beast's genetic potential but with the unshakable will to be the best and that will work until he passes out and then wake up and go for more. that second guy will be a less motivated guy quite often. *bodybuilding, football, mma are great examples of this I think.

Now that being said, you take that genetic beast , and one that has incredible never ending work ethic and drive, well then that second guy is most likely just screwed

Shorter guys have very compact muscle Jay I think was 5-8 maybe. I'm 6-3 and my muscles are very long and thick but nowhere near as nice looking as someone shorter with more compact muscles. So I'd say his height, work ethic, passion, genetics, drug intake but more importantly a shit ton of proper food and caloric intake.

Some say hard work beats genetics but if you're doing the work and and have the genetics as well it's gonna be a win win situation all round.

I think when people say genetics, they are saying the physical aspect of that. I believe its much more than that. I believe "genetics" encompasses every aspect of their being. Mentally and physically. They emulate their craft from head to toe, inside and out, just as any elite athlete does. These guys and gals have the mental fortitude to push through painful plateaus in a way we do not. They recognize their gift and exploit it beyond human leagues. They are inhuman in a sense.

I'll be the first to tell you I lift with utter intensity. To the best of my ability. Each and everytime. My best doesn't reach the realm of a pro in any way shape or form. That saying, "born to do this", is what they have found and honed and manipulated skillfully to reach the godly level they were meant to stand upon.

When you watch videos of them lifting, they are in a different realm! It is as plain as day the pain they endure mentally as well as physically on their journey. Our last rep struggled on is their starting point. They are machines! Just as any top athlete is. Their survival is the craft! It would take being one to understand the outcome. We can all be the very best representative of ourselves no doubt. But in all honesty we weren't absolutely meant to walk the same path as them. We all have our born with skill, some, just like bodybuilders, are diligent in becoming one with it!

He got that way by absolute proper hard work in the gym and an absolute perfect diet watch his videos mate his whole life was bidy building pure dedication.... and yes of course perfectly planned and run cycles of steroids- peps- growth- diuretics and of course the the taboo subject you mentioned. Even a bit of synthol. But mainly his dedication and food. Mixed with genetics. All this everyday over many years.

Its genetics. Love it or hate,,,people hate to admit it,,,but its true. Ive worked closely with numerous athletes over the years and we are all not created equal.

Well bro, myostatin-related muscle hypertrophy is genetic and inherited and rare. I don't know what the test is for it, nor do I know if Jay Cutler has the gene for it. He may not even know or care. Clearly, we don't have any methods to induce this in adults as of yet. Scholarly articles often bore me but there are plenty of links to them on the general internet for you to read. Big Ramy may be another example of this condition.