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  #1  
Old 07-14-2011
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Genetics Mitochondrial Inheritance & a Genetic Pedigree

In the family represented by the pedigree, affected persons have a disease characterized by mitochondrially inherited late onset optic atrophy. Assuming that the family and personal medical history of the partner is unremarkable, the risk of optic atrophy to develop in THE male child of IV-9 is

Mitochondrial Inheritance & a Genetic Pedigree-pedigree.jpg
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  #2  
Old 07-14-2011
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Default No chance

IV - 9 means affected male child in 4th generation. Since it is given that disease has mitochondrial in heritance, it can only be transmitted from affected female. And From pedigree also it is obvious that only children of affected females are affected. Therefore the male child of IV - 9 will not develop the disease.

The reason for such inheritance is that the genes for the disease are carried as mitochondrial genes and during gamatogenesis the mitochondria of sperm gets degenerated and only maternal mitochondria is inherited in offspring.

Please correct me if I am wrong.

Thanks.
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Old 11-25-2015
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Show Teeth

Quote:
Originally Posted by ntp0015 View Post
IV - 9 means affected male child in 4th generation. Since it is given that disease has mitochondrial in heritance, it can only be transmitted from affected female. And From pedigree also it is obvious that only children of affected females are affected. Therefore the male child of IV - 9 will not develop the disease.

The reason for such inheritance is that the genes for the disease are carried as mitochondrial genes and during gamatogenesis the mitochondria of sperm gets degenerated and only maternal mitochondria is inherited in offspring.

Please correct me if I am wrong.

Thanks.
i m agree with explanation

Last edited by Netgear; 11-25-2015 at 12:00 PM. Reason: misunderstood
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  #4  
Old 06-06-2016
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Smile

great visual representation. Gives me a better understanding of the pedigree
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