This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: AIIMS 2019, Subject name: Biochemistry
In which of the inheritance, if father is affected no offspring is affected, but if mother affected, all offspring affected? 
Select and explain. 
A. Mitochondrial, B. X linked recessive, C. Autosomal dominant, D. Autosomal recessive
A: Mitochondrial
Answer: A: Mitochondrial 
Explanation: Mitochondrial Inheritence Mitochondria is derived only from mother Mitochondrial disease has high incidence as : - Mitochondrial DNA repair cannot occur - Introns are not present - Continuous exposure to the oxygen free radicals Therefore have more chances of mutations in mitochondrial DNA Mitochondrial Inheritence Affected mother will transmit disease to all offsprings X linked disease No male to male transmission Y linked disease Affected father will transmit disease to all son Autosomal disease Equal frequency of these disease in male and female