12-12-2005, 04:57 PM
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
© Deletion of the short arm of chromosome
11
(D) Nondisjunction of chromosome 18
(E) Nondisjunction of chromosome 21
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
© Deletion of the short arm of chromosome
11
(D) Nondisjunction of chromosome 18
(E) Nondisjunction of chromosome 21