Mutations in the genes encoding collagens often have detrimental consequences, resulting in severely crippling diseases. Particularly devastating are mutations that change glycines, which are required at every third position in the collagen polypeptide chain so that it can assemble into the characteristic triple-helical rod (see Figure 20–9). Would you expect collagen mutations to be detrimental if only one of the two copies of a collagen gene is defective?

Figure 20–9

Transcribed Image Text:

single collagen polypeptide chain N triple-stranded collagen molecule collagen fibril 0.5-3 μm collagen fibers 263 1.5 nm 10-300 nm 1 μm