Does this sentence make sense?

It's kind of a weird, nonsensical notion to begin with. I am assuming from the information given that you want to list the number of diseases where humans have allegedly God-given (yes, you would hyphenate those two words if appearing together) immunity. Which is a concept that makes no sense at all - your immune system is a holistic part of your body and it cannot be divided into the parts that are "God-given" and those that aren't. It's an all or nothing proposition.

I can number the diseases on one hand where there's God-given immunity.

Still a bad sentence. The concept is incorrect scientifically and the sentence structure is tortured.

There are few if any diseases where our immunity is God-given.

That's a bit closer to reality, but it still stinks.

Here's a hint - don't talk science in light of God or vice versa. Belief systems, by definition, are unproven. They are faith-based and faith, by definition, is something accepted in the absence of concrete proof. Science, on the other hand, is composed of hypotheses that are tested in the context of theories. Good theories stand the test of time, and are continually tested by other hypotheses and experiments. If more information comes to light, then theories are adapted and changed, or they may be discarded altogether. For example, we used to think that the atom was the smallest unit of matter, until we were able to start splitting them. Then we thought electrons and protons and neutrons were the tiniest things, until quarks were postulated, and evidence of their existence was found via colliders. There may even be units of matter that are smaller than these, but we cannot detect them yet. If such units are found, then our theory will change again. This is how science works. It doesn't have diddly to do with faith or God - and it isn't a threat to either, I might add. The two can coexist so long as no one goes around trying to explain one with the other. It's like trying to explain how to make a casserole by using the rules of baseball.

Can you elaborate on the part of "Write the diseases"? without considering God-given immunity part?

Does it make sense when I say "I want to write the diseases." instead of I want to list the number of diseases"?

Thanks a lot.

Use "write down" since you are making a list.

Or just use list as your verb.

No it doesn't! Forget the God and use list as a verb, like someone already mentioned.

The sentence still wouldn't make sense.

You can list the diseases with God-given immune systems.

If you say so. I don't agree.