Why do some people have blue eyes?

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Tags

1. #called
2. #ability
3. #single
4. #affecting
5. #amount
6. #turned
7. #depends
8. #switch
9. #chromosomes
10. #color
11. #produce
12. #melanin
13. #resulted
14. #pigment
15. #brown
16. #which
17. #literally
18. #mutation
19. #creation
20. #genetic