I considered the idea that we are born spiritual and develop our spirituality depending on which culture we grew up in. I considered this both while in college, and later when I became Buddhist. I think it's a valid one which I eventually came to disagree with (although I can understand the perspective).
This is why. I do believe, as most Buddhists do, that we are connected to each other and the entire universe on some level, and we know that instinctively, as we are empathetic creatures. Yet the story of a god (whatever that god may be) is not instinct. It is the result of a history of the human race trying to understand things they do not understand, using some "perfect" or "extreme" version of themselves or the things around them to to explain them. The use of a god figure had then evolved as a way to control as well.
We are all born atheist - that doesn't mean we aren't connected in some way (that even science says is true, as we share the same particles as long-dead suns and breathe each others' dead skin cells), or that we aren't innately aware of that connection - only that the idea of God is not something anyone just believes because we have some innate God-believing-gene, but because it's taught to us.