Inherited Disorders

Question 0

Achondroplasia: affects what zone? Tx?

Answer 0

Hypertrophic. CNP analog.

Question 1

Achondroplasia: characteristics. Inheritance. Defect. Pelvis.

Answer 1

Rhizomelia. Kyphosis. Trident hand. AD but 80% de novo. GOF FGFR3 neg regulator of chondrocytes. Horizontal acetabular roof

Question 2

Osteogenesis imperfecta: defect? Characteristics?

Answer 2

Mutation in COL1A1 & 2. Abnormal type 1 collagen (alpha 1 or 2 chain). Brittle bones, blue sclera.

Question 3

Which demonstrates haploinsufgiciency and dominant negative mutations

Answer 3

OI

Question 4

Ehlers danlos syndrome: features? Defect?

Answer 4

Delayed motor milestones, skin tears easily, MVP. COL5A1 or 2 (type 5 collagen) mutation. Null allele results in haploinsifficiency

Question 5

Marfans: features?

Answer 5

Arachnodactyly, ectopia lentis, CV problems. Armspan>ht. scoliosis.

Question 6

Marfans: defect? TGF-b?

Answer 6

Fibrillin1 which is scaffold of elastic tissue. Normally binds TGF-b so in MS you get excess TGF