Which principle explains why rare deleterious mtDNA mutations may be lost in one generation despite being present in the mother?
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Correct answer: The bottleneck effect during oogenesis
During oogenesis, only a small subset of mtDNA molecules is transmitted to each egg; this “bottleneck” may randomly exclude some mutant genomes, so offspring can inherit mostly normal mtDNA despite maternal mutation.
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More Mitochondrial inheritance questions
- Which of the following is a potential challenge when diagnosing mitochondrial diseases using family history alone?
- Which of the following statements about nuclear-encoded mitochondrial proteins and their inheritance is correct?
- Which mitochondrial feature makes mtDNA a useful tool for tracing human maternal ancestry over many generations?
- Which of the following would be strong evidence for a nuclear (rather than mitochondrial) cause of a suspected mitochondrial disease?
- Why might a heteroplasmic mother have both affected and unaffected children when carrying a deleterious mtDNA mutation?
- Which inheritance pattern best describes transmission of mutations in mitochondrial DNA (mtDNA) in humans?