Types of collagen

Question 1

A 24-year-old woman presents to her GP with low back pain. She is otherwise fit and well. During her childhood, she reports a number of fractures of fingers and wrists. The patient explains that both her father and sister have had multiple fractures throughout their lives too.

On examination, she appears to have scoliosis and paralumbar tenderness. She has blue-grey sclera.

Given the likely diagnosis, a mutation in which type of collagen is responsible?

Answer 1

type 1

Question 2

a mutation in type 1 collagen, which is the main component of the organic part of bone, as well as skin and tendons. what diagnosis could it be

Answer 2

osteogenesis imperfecta

Question 3

type 2 collagen is the main component of what

Answer 3

cartilage

Question 4

type 1 collagen is the main component of what

Answer 4

bone, skin and tendons

Question 5

what problem could be caused by mutation in type 2 collagen

Answer 5

chrondodysplasias

Question 6

type 3 collagen is main component of what

Answer 6

reticular fibres

leads to Ehlers danlos syndrome

Question 7

type 4 collagen forms what

Answer 7

basal lamina

mutations in this may causes alports syndrome and good pastures syndrome

Question 8

type 5 collagen is found in

Answer 8

cell surfaces, hair and placentas

Question 9

mutations or disorders include classical variant of what syndrome ( same as type 3 )

Answer 9

Ehlers dances syndrome

Question 10

Ehler-Danlos syndrome is an autosomal dominant connective tissue disorder that mostly affects type III collagen. This results in the tissue being more elastic than normal leading to joint hypermobility and increased elasticity of the skin.

Features and complications

Answer 10

elastic, fragile skin
joint hypermobility: recurrent joint dislocation
easy bruising
aortic regurgitation, mitral valve prolapse and aortic dissection
subarachnoid haemorrhage
angioid retinal streaks