Mitochondiral genetics Flashcards
What is homoplasmy in mitochondria
All copies of mitchondiral genome are the same
What is heteroplasmy in mitochondria
More than one type of mitochondrial genome present
Why can mitochondrial diseases have nuclear origins
Nuclear proteins are involved in the function of mitochondria
Describe the features of a mitochondrial disease caused by nuclear genome mutations
Same inheritance patterns as Mendelian disorders
Caused by defects in genes involved in replication, transcription, translation and repair of mitochondrial DNA
How does damage to Parkin/PINK1 pathway lead to parkinsons
Normally PINK1 is imported into the mitochondria, cleaved and released; but damage to mitochondria causes depolarisation of membranes, so PINK1 accumulaties in the outer membrane of MT which cases Parking to be recruited into mitochondria triggering autophagy. Build-up of disfunctional mitochondria
What is the link between mitochondrial diseases and cancer
Cancerous tumours produce excess lactte in the presence of oxygen (Warburg effect); high rate of glucose uptake by solid tumours is used for diagnosis; evidence of defective mitochondria
What effect does mtDNA have on tumour development
Cells without mtDNA show slower tumour formation