Young: Medical Genetics - Extended Matching Questions

Table of Contents

1. Chapter 5
   1. Question 1
   2. Question 2

Question 1

Instructions: Each group of extended matching questions consists of lettered options followed by a list of numbered problems/questions. For each numbered problem/question select the one lettered option that is most closely answers the question. You can use the lettered options once, more than once, or not at all.

Theme: Genes for Mendelian disorders: causal genes

Options:

1. Cathepsin K
2. FMR1
3. Dystrophin
4. Huntingtin
5. CYBB
6. Fibrillin
7. CFTR
8. Hamartin

Each of the patients below has a genetic disorder. Select the gene which is most likely to be mutated from the options.

1

Scenario 1   A 12-year-old boy who first presented with difficulty walking at age 5 years and now has to use a wheelchair. Choose... Cathepsin K FMR1 Dystrophin Huntington CYBB Fibrillin CFTR Hamartin The diagnosis is Duchene muscular dystrophy. Dystrophin protein is located close to the muscle membrane where it is part of a glycoprotein complex linking intracellular actin with extracellular laminin. See Page 111.Incorrect. See Page 111.Your answer has been saved.

2

Scenario 2   A 37-year-old man who has a scoliosis and is admitted to the cardiac unit for surgery to his aortic root. Choose... Cathepsin K FMR1 Dystrophin Huntington CYBB Fibrillin CFTR Hamartin This man has Marfan syndrome, in which the most serious complication is an aortic aneurysm. Fibrillin is a major structural component of extracellular microfibrils. See Page 106.Incorrect. See Page 106.Your answer has been saved.

3

Scenario 3   A 12-year-old girl with diabetes mellitus and a history of recurrent severe respiratory infection. Choose... Cathepsin K FMR1 Dystrophin Huntington CYBB Fibrillin CFTR Hamartin Approximately 5% of children and young adults with cystic fibrosis develop diabetes mellitus. CFTR encodes a chloride channel. See Page 107.Incorrect. See Page 106.Your answer has been saved.

4

Scenario 4   A 3-year-old boy with autistic features and moderate to severe developmental delay. Choose... Cathepsin K FMR1 Dystrophin Huntington CYBB Fibrillin CFTR Hamartin This is a common presentation in the Fragile X syndrome, which is caused by expansion of a triplet repeat in FMR1. FMR1 encodes a protein which regulates mRNA translation in the brain. See Page 112.Incorrect. See Page 112.Your answer has been saved.

5

Scenario 5   A 47-year-old man with memory loss and involuntary movements. Choose... Cathepsin K FMR1 Dystrophin Huntington CYBB Fibrillin CFTR Hamartin The initial presenting features in Huntington disease can be quite subtle and some patients have been wrongly accused of alcohol intoxication. The Huntington disease gene encodes a protein which accumulates as a neurotoxic aggregate in brain cells. See Page 105.Incorrect. See Page 105.Your answer has been saved.