PATHOLOGY MCQ
GENETICS AND DISEASE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Which of the following situations is most usual for a dominant allele that results in severe effects in the offspring?
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both parents have the trait
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the trait occurs by mutation
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only a single offspring has the trait
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none of these
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Explanation:
Detailed explanation-1: -Very few genetic disorders are caused by dominant mutations because these alleles are less likely to be passed on to successive generations. Nondisjunction is the failure of replicated chromosomes to separate properly during meiosis. This may result in genetic disorders caused by abnormal numbers of chromosomes.
Detailed explanation-2: -Autosomal dominant inheritance: A person affected by an autosomal dominant disorder has a 50 percent chance of passing the altered gene to each child. The chance that a child will not inherit the altered gene is also 50 percent.
There is 1 question to complete.