Lecture 8

Question 1

Neurofibromatosis

Answer 1

occurs following the mutation of neurofibromin gene on chromosome 17 q11.2

Question 2

What is the most common autosomal dominant inheritance disorder in US?

Answer 2

Nuerofibromatosis (von Recklinghausen disease)- both males and females equally affected

Question 3

Type 1 neurofibromatosis

Answer 3

multiple neurofibromas on the skin arising from schwann cells of peripheral nerves- cafe au lait spots present

Question 4

Type 2 neurofibromatosis

Answer 4

bilateral acoustic neuroma on 8th nerve with balance problems and hearing loss

Question 5

Most common form of muscular dystrophy?

Answer 5

Myotonic dystrophy

Question 6

What type of inheritance is myotonic dystrophy?

Answer 6

autosomal dominant inheritance

Question 7

What does myotonic dystrophy exhibit?

Answer 7

anticipation– each generation occurring earlier and earlier

Question 8

FOrm of MD transmitted by mother only and present at birth?

Answer 8

congenital form

Question 9

What does MD present with?

Answer 9

usually present in adult life- slowly progressive weakness and myotonia- defect in gene for increased muscle tone
cataract, dysphagia conduction defect in heart
myopathic facies in congenital form

Question 10

Myopathic face

Answer 10

face of baby is round and puffy

Question 11

What is Achondroplasia

Answer 11

dominant inherited congenital disorder- mutation of fibroblast growth factor 3 at chromosome 4p

Question 12

What does defective fibroblast growth factor cause?

Answer 12

abnormality of cartilage formation resulting in stunted growth- no mental or health deformities