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Discussion Starter #1
A 4-month-old female is brought to her pediatrician by her mother who is concerned about some photographs she recently had developed. In the photographs, only the child’s right eye demonstrates a red reflex. Examination of the left eye confirms absence of a red reflex. Which of the following mechanisms is most likely involved?

a- Deletion in the long arm of chromosome 13
b- Deletion in the short arm of chromosome 5
c- Deletion of the short arm of chromosome 11
d- Nondisjunction of chromosome 18
e- Nondisjunction of chromosome 21
 

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Discussion Starter #5
Because of a Retinoblastoma cataract?
There's no cataract in retinoblastoma
It's the retinoblastoma itself that causes the loss of red reflex (Leukocoria)

Option C is the real distractor as it's pointing to another tumor suppressor gene of Wilm's tumor which may cause aniridia (WAGR association)
 

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Right... leukocoria, not cararact. Thanks. True about the aniridia and WAGR. Good question.

There's no cataract in retinoblastoma
It's the retinoblastoma itself that causes the loss of red reflex (Leukocoria)

Option C is the real distractor as it's pointing to another tumor suppressor gene of Wilm's tumor which may cause aniridia (WAGR association)
 
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