Maybe one should ask oneself how your view of talent affects yourself? How will your view benefit yourself?
If you decide that (this somewhat diffuse concept of) talent exists and is a factor you better decide that you are madly talented, gods gift to whatever you do. No need to check with reality.
If you think you lack in talent still you will probably continue doing what you like to do, as in this case write music. But that attitude might eventually make you perform worse and worse, or at least make things go slow, and thus prove to yourself that you lack talent.
Of course there are differences in how easily we grasp things, but my opinion is that very many can become great at what they decide to do, and for a few it will be difficult. By great I mean create great things, not become an icon remembered for hundreds of years. Once a field is chosen time is important. If you start at the age of three you will have a lot of experience when it is time to become professional. Then you need to surround yourself with the right environment so you get inspired and so you eventually give chance a possibility to make you very successful.
Since the phenomena music a cultural product and not something genetical, all science proves that, there can not be something as "genetic talent tagged for music". If I would give "talent that matters" a definition it would be ability to relax and believe in yourself and the ability to dedicate yourself to a task. If you can do this, you can perform great in your chosen area, save if you happen to have real difficulties for this area.
:)