GENETICS AND EVOLUTION
GENETIC BASIS OF INHERITANCE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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AIDS
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Down syndrome
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Sickle-cell anemia
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Hemophilia
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Detailed explanation-1: -Hemophilia is a sex-linked recessive disorder. The abnormal gene responsible for hemophilia is carried on the X chromosome.
Detailed explanation-2: -Hemophilia is an X-linked recessive hereditary disorder that classically affects males due to the presence of only one X chromosome in males. Females are usually carriers due to the presence of counterpart X chromosome, but many times manifestations of hemophilia are seen in heterozygous carrier females.
Detailed explanation-3: -It almost always is inherited (passed down) from a parent to a child. Both hemophilia A and B are inherited in the same way, because both the genes for factor VIII and factor IX are located on the X chromosome (chromosomes are structures within the body’s cells that contain the genes).