the relative amounts of type iii and type i collagen , determined as the ratio of their constituent alpha 1 ( iii ) and alpha 1 ( i ) chains , have been measured by interrupted electrophoresis of pepsin extracts of skin collagen from 31 patients with osteogenesis imperfecta of varying severity , and from six clinically unaffected family members .
C0041455
type i collagen
C0009325
collagen