Payne, B. A. et al. (2013) present evidence that a low l...

Question

Payne, B. A. et al. (2013) present evidence that a low level of heteroplasmic mtDNA exists in all tested healthy individuals.

What genetic conditions within a given mitochondrion are likely to contribute to such a variable pool of mitochondria?

Accepted Answer

Hello everyone. Let's look at our next question. It says my a chronic epilepsy and ragged red fiber disease. M. E. R. R. F. Exhibit maternal inheritance which of the following about M. E. R. R. F. Is therefore true. So what would maternal inheritance be? Well this would be essentially a trait inherited only from the mother. So we're used to thinking of say excellent traits which tend to be passed from mother to son. But in this case it's just specifically a trait inherited only from the mother. And what would cause that? Well when we recall that fertilization the cytoplasmic components of the cell only come from the egg cell. The sperm only donates its nuclear DNA. So that means anything inherited from extra nuclear D. N. A. Uh specifically most commonly of course mitochondrial D. N. A. Ah since the mitochondria have their own D. N. A. And that's inherited only from the mother. So let's look through our answer choices with this in mind. Choice A. Says the offspring of an inherited father can inherit the disease. However we just discussed maternal inheritance means it's only inherited from the mother. It's the DNA. Does not come from the father. And therefore choice A. Cannot be correct. Choice B. Says the offspring of an affected mother can inherit the disease and that is true. So we're going to select that is our answer. We don't have a choice of more than one correct answer but we'll keep going to be thorough here. Choice C. Says it can be inherited by the offspring even if both parents are unaffected. Well this would be incorrect. It has to be inherited from the mother. So if the mother is unaffected the disease won't be passed on. And then Choice D. Says the disease can be passed only if both parents are affected. And again this is not true. That would be true of say a recessive disease but in this case it's inherited directly from the mother. So it doesn't matter what the status of the father is, only the mother's status. So again if a disease like M. E. R. R. F. Because of its maternal inheritance which the following about it must therefore be true. Choice be the offspring of an affected mother can inherit disease. See you in the next video.

Payne, B. A. et al. (2013) present evidence that a low level of heteroplasmic mtDNA exists in all tested healthy individuals.

What genetic conditions within a given mitochondrion are likely to contribute to such a variable pool of mitochondria?

Key Concepts

Heteroplasmy

Mitochondrial Inheritance

Mitochondrial Dynamics

Watch next

Payne, B. A. et al. (2013) present evidence that a low level of heteroplasmic mtDNA exists in all tested healthy individuals.What genetic conditions within a given mitochondrion are likely to contribute to such a variable pool of mitochondria?

Key Concepts

Heteroplasmy

Mitochondrial Inheritance

Mitochondrial Dynamics

Watch next

Payne, B. A. et al. (2013) present evidence that a low level of heteroplasmic mtDNA exists in all tested healthy individuals.

What genetic conditions within a given mitochondrion are likely to contribute to such a variable pool of mitochondria?