Finger Nail Stipe

I have a orange/tan stripe down my finger nail on my right ring finger.  There is no pain.  I have had it for a few years and the nail continues to grow with the colored stripe.  I am concerned that it could be Melanoma.  A doctor just did a biopsy from under the nail, but still waiting for the results.  I had a great aunt who died from Melanoma that started in her toe nail and it metasticised.  If the biopsy comes back negative, I am not sure what they will do to find out what is causing it.  None of my other nails have any problems.  I have never injured the nail that I am aware of.  I am scared because I have let it go so long thinking it might just be a vitamin deficiency or something.