Genetic Variation in Coding Regions
The remaining SNPs occur in coding regions. They may alter the protein made by that coding region, which in turn could influence a person's health.
Some of the variations that occur in the coding and regulatory regions of genes simply contribute to the normal variation observed among people. They can, for example, change the way a person looks. Some people have blue eyes, others brown; some are tall, others short.
Other variations in coding regions are harmless because they occur in regions of a gene that do not affect the function of the protein made.