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Mitochondrial diseases can be caused by genetic mutations in the body's nuclear DNA. Mitochondrial diseases are a group of disorders that affect the function of mitochondria, which are the energy-producing structures within cells. While mitochondria have their own DNA (mtDNA), the majority of their genetic material is located in the cell's nucleus (nuclear DNA). Mutations in both nuclear DNA and mtDNA can contribute to mitochondrial diseases. Here are some examples of mitochondrial diseases caused by mutations in nuclear DNA: Leigh Syndrome: Leigh syndrome is a severe neurological disorder that can be caused by mutations in nuclear DNA. Mutations in genes involved in mitochondrial function, such as genes encoding proteins required for mitochondrial assembly or maintenance, can lead to impaired energy production and neurological symptoms. NARP Syndrome: Neuropathy, Ataxia, and Retinitis Pigmentosa (NARP) syndrome is caused by mutations in nuclear DNA. This disorder affects multiple systems, including the nervous system and the eyes, and is often associated with a decreased ability of mitochondria to produce energy. Pyruvate Dehydrogenase Complex Deficiency: This disorder is caused by mutations in genes that encode components of the pyruvate dehydrogenase complex, which is crucial for energy production. Mutations in nuclear DNA affecting this complex can lead to a buildup of lactic acid in the body and neurological symptoms. Coenzyme Q10 Deficiency: Coenzyme Q10 (CoQ10) is a molecule essential for mitochondrial function and energy production. Mutations in nuclear DNA affecting genes involved in CoQ10 biosynthesis or utilization can result in CoQ10 deficiency and mitochondrial dysfunction. Mitochondrial Myopathy: Some forms of mitochondrial myopathy can be caused by mutations in nuclear DNA. These mutations can affect proteins involved in muscle cell function and energy production, leading to muscle weakness and other symptoms. Complex I Deficiency: Complex I is a part of the electron transport chain in mitochondria, and mutations in nuclear DNA affecting genes encoding its components can lead to Complex I deficiency, resulting in energy production deficits and mitochondrial disease. Barth Syndrome: Barth syndrome is an X-linked genetic disorder caused by mutations in a nuclear DNA gene called TAZ. It affects various systems in the body, including the heart and skeletal muscles, leading to muscle weakness, cardiomyopathy, and other symptoms. These examples illustrate how mutations in nuclear DNA can disrupt mitochondrial function and lead to various mitochondrial diseases. It's important to note that mitochondrial diseases can result from a complex interplay of genetic factors, including mutations in both nuclear DNA and mtDNA, as well as environmental factors. Questions: Which of the following options is the most likely explanation of the above pedigree. A) Autosomal Recessive B) Mitochondrial C) X-linked recessive D) Autosomal Dominant E) Y-linked In the previous question, autosomal dominant was a potential answer that could fit the pattern of affected individuals. If we assume that this condition is inherited in an autosomal dominant way, then what was the likelihood that all 5 of the third generation offspring in the single family were affected? A) 1/32 B) 1/8964 C) 1/2 D) 1/1024 E) 1/10 Mitochondrial disease can manifest due to mutations in the genomic or mitochondrial DNA. Therefore the phenotype of the disease isn’t sufficient to predict the inheritance pattern. However, which of these symptoms might increase your suspicions that this is a sign of mitochondrial mutation? There are multiple correct answers here, can you get them all? A) muscle weakness B) developmental delay C) vision problems D) scleroderma E) arthritis F) gout G) asthma H) poor growth
