MadSci Network: Anatomy |
David - I'm not sure how helpful my answer will be but here goes! Some variation in finger nails, as well as in everything else, is due to our individual genetic heritage. Other variations are due to diet and certain disease conditions. The closest I can come to your question is that it may be a nutritional deficiency, but what nutrient, I don't know. An iron deficiency, for example, can cause a curvature of the nail at its tip. I realize that your question was regarding vertical grooves and the bottom line is that I don't know their cause. I can be relatively sure that it is normal and nothing to be concerned about. If this is not a satisfactory answer, re submit it and someone else may get to answer it with a more definite answer.
Try the links in the MadSci Library for more information on Anatomy.