Dentin is mostly made of collagen, the main structural protein in skin and other connective tissues. (sciencedaily.com)
The trait appears to be genetic and is a result of variation in collagen, the main structural protein of connective tissue. (scientificamerican.com)
In this syndrome, cells of the immune system infiltrate the heart muscle and misinterpret myosin, the main structural protein of heart muscle, as being a foreigner. (joslin.org)