Naked Science Forum
Life Sciences => Physiology & Medicine => Topic started by: Igor on 01/03/2008 09:54:10
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Is it possible for a vertically transmitted infection to skip a generation ?,
i.e. the 1st & 3rd generations being symptomatic, but the 2nd generation is an asymptomatic carrier of the microbe.
Any examples of this phenomenon in humans or other animals ?
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Is it possible for a vertically transmitted infection to skip a generation ?,
i.e. the 1st & 3rd generations being symptomatic, but the 2nd generation is an asymptomatic carrier of the microbe.
Any examples of this phenomenon in humans or other animals ?
Are you actually talking about an infection of a genetically inherited trait?
If it is an infection, then why would it be limited to vertical infection?
Genetically inherited traits may not manifest themselves in every generation (depending on other genetic considerations), but they are not infections.
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I was talking about microbial infections: viral, bacterial, fungal, amoebic.
(I understand about recessive genes skipping generations).
If it is an infection, then why would it be limited to vertical infection?
In the scenario I was thinking of the 1st generation had never met the 3rd but had transmitted the infection to them via an asymptomatic 2nd generation. So horizontal transmission from 1st to 3rd would not be possible.
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If it is an infection, then why would it be limited to vertical infection?
In the scenario I was thinking of the 1st generation had never met the 3rd but had transmitted the infection to them via an asymptomatic 2nd generation. So horizontal transmission from 1st to 3rd would not be possible.
Firstly, that does not explain why horizontal infection could not happen through an intermediate vector, even if the individuals had not actually met (through an uncle, or some unrelated person).
But that aside, the manifestation of a disease is an interaction between the disease causing agent, the environment (e.g. nutrition), and the genetics of the person involved. It is quite plausible (although how likely: I cannot say), that either environmental or genetic factors for the intermediate generation may suppress the symptoms of the disease (or at least to reduce the manifestation to an unnoticeable level), while allowing the disease causing agent itself to be transmitted to the next generation that has a different environmental or genetic interaction with the disease causing agent.