The organ that can be spared in Mitochondrial disorders is

Mitochondrial Inheritance An individual's mitochondrial genome is entirely derived from the mother because sperm contains few mitochondria, which are typically shed upon feilization. It follows that mitochondrial disorders exhibit maternal inheritance. A woman with a mitochondrial genetic disorder can have affected offspring of either sex, but an affected father cannot pass on the disease to his offspring.The mitochondria are the cell's suppliers of energy, and the organs that are most affected by the presence of abnormal mitochondria are those that have the greatest energy requirements, such as the brain, muscle, hea, and liver Common manifestations include developmental delay, seizures, cardiac dysfunction, decreased muscle strength and tone, and hearing and vision problems. Examples of mitochondrial disorders include MELAS (myopathy, encephalopathy, lactic acidosis, and stroke-like episodes), MERRF (myoclonic epilepsy associated with ragged red fibers), and Kearns-Sayre syndrome (ophthalmoplegia, pigmentary retinopathy, and cardiomyopathy)Reference: Nelson Textbook of Paediatrics; 20th edition; Chapter 80; Patterns of Genetic Transmission