Expert: Walter Hintz - 6/3/2006

Question
This is my biology homework.  I'm allowed to ask anybody I want as long as I quote you.  

Cytochrome b deficiency:  Cytochrome b is part of the electron transport chain in mitochondria.  In this rare genetic disorder, only the mitochondria in the muscle are affected.  Very early in their embryonic development, a mutation occurred in the cytochrome b gene in a cell destined to produce the muscles.  How will cell respiration be affected?  What symptoms will be observed?  What will be observed during mild exercise?
I think that since only glycolysis and the Krebs cycle will work, they will experience lactic acid build-up during the slightest exertion.  Extreme muscle soreness and fatigue will be the result.  Do you agree?
Thank you!

Answer
Hi Sal:  I do not know much about cytocrome b deficiency but lack of muscle mitochondria could cause a problem since it would affect fermentation. In the anaerobic situation taht occurs in muscles pyruvate is metabolized by fermentation and the byproduct is lactate.  If fermentation is not happening there would be less lactate, not more.