Do individuals have a telos?

Have humans been created with a specific purpose? The more I think about the issue of the human in the posthuman world, the larger this question looms for me. One of the ways to begin to think about the question would be to make a distinction between Aristotelian telos and a Christian one. As far as I know (and I'm no philosopher), Aristotle believed that each species of creature has within in it certain potentialities, and the goal of an individual's life would be to reach the highest potential for your species. For humanity, it would be measured by the attainment of virtues. Christians (as St. Thomas pointed out) would agree a great deal with Aristotle, but it does change things to begin with a personal God. I believe that being created by such a God would mean a few things for certain: we are not the creator; we are, therefore, limited; and our relationship to God constitutes who we are fundamentally. But what does that mean exactly when it comes to the issue of purpose? Is it right to speak of God's specific purpose for my individual life? Or are his purposes general, with a wide range of possible outcomes? The reason why it matters is that if I were born with mental deficiencies, would my purpose be different? Is our telos so general (the chief end of man is to glorify God and enjoy him forever) that any human person could fit it? I think it is essential for us to make room in our definition of the human for every person, from the child with Down's syndrome to smallest embryo. Clearly, God allows suffering; he also allows a wide range of abilities and disabilities in humanity. Do all of these exist for a purpose?