Medical Genetics Inheritance During fertilization mtDNA is derived only from the oocyte; Maternal inheritance: mtdNA mutations transmitted only from mother Mutations transmitted to all offspring Male femalei Increased mutant mtdNa in the mothers blood increased Frequency of affected offspring Risks of having affected offspring differ between different mtDNA mutationsMedical Genetics Inheritance • During fertilization mtDNA is derived only from the oocyte; • Maternal inheritance: mtDNA mutations transmitted only from mother; • Mutations transmitted to all offspring, Male & Female; • Increased Mutant mtDNA in the mothers' blood increased Frequency of affected offspring • Risks of having affected offspring differ between different mtDNA mutations