True about mitochondrial inheritance
Ans. b (An offspring bom to an affected female will be affected) (Ref. Nelson paediatrics, Ch. 80. p. 496)Mitochondrial Inheritance# An individual's mitochondrial genome is entirely derived from the mother. Sperm contain few mitochondria, most of which are shed upon fertilization.# Mitochondrial disorders exhibit maternal inheritance; a woman with a mitochondrial genetic disorder will have only affected offspring of either sex, while an affected father will have no affected offspring.# Common manifestations include developmental delay, seizures, cardiac dysfunction, i strength and tone, as well as hearing and vision problems.# Examples include- NARP- MELAS (myopathy, encephalopathy, lactic acidosis, and strokelike episodes),- MERRF (myoclonic epilepsy associated with ragged red fibers),- Kearns-Sayre syndrome (ophthalmoplegia, pigmentary retinopathy, and cardiomyopathy).# Cells may contain a mixture of mutant and normal mitochondria, referred to as heteroplasmy.
An offspring bom to an affected male will be affected
An offspring born to an affected female will be affected
An offspring born to an affected female will be normal
All of the above
Genetics And Genetic Disorders