mash
Forum Fanatic
Topics: 147
Posts: 1,326
|
A patient with the Marfan's syndrome is evaluated at a clinic. He is noted to have a tall, thin body habitus, loose joints, and arachnodactyly (spider fingers). Ophthalmologic examination reveals lens dislocation. Echocardiogram reveals dilation of the aortic root. A family history reveals that the patient's parents are medically normal, but that his paternal grandfather and great-grandfather died in their forties with lens dislocation and dissecting aortic aneurysms. A sister is found to have a similar body habitus, dilation of the aortic root, and normal lenses. The different findings in these different family members with the same disease are best described by which of the following terms?
A. Pleiotropy
B. Founder effect
C. Variable expressivity
D. Incomplete penetrance
E. Genetic heterogeneity
___________________
I hear and I forget. I see and I remember. I do and I understand.
--Confucius
|
| piter
Forum Elite
Topics: 34
Posts: 191
|
D. Incomplete penetrance
|
| intern_doc
Forum Guru
Topics: 98
Posts: 433
|
I thought that Marfan is an example of Pleiotropy ? But in the question above seems NOT to fit the description. Sounds more like incomplete
Now I am confused
___________________
Please call me by my first name on March 17 - Dr.
|
| piter
Forum Elite
Topics: 34
Posts: 191
|
u r right marfan is an example of pleiotropy, but the q is about penetrance. It can be also with variable expressivity and still one gene is responsible for that (pleiotropy).
|
| uscan
Forum Senior
Topics: 19
Posts: 88
|
Confused :?
-When comparing the patient and his sister-----variable expressivity
-When talking about his father who got the mutant gene but has normal phenotype-----incomplete penetrance
|
|
| |
| | | | | |
