The long-awaited demonstration of selective male mitochondria destruction has several implications. This escape may also explain the notorious poor condition of newborn cloned mammals, which may be due to heteroplasmy, the phenomenon of two mitochondrial populations fighting for control in a cell. Consequences for humans may be imminent. Women over 40, who ostensibly have eggs with aged cytoplasm, are treated by microinjection of their eggs with cytoplasm from eggs donated by younger women. Some pregnancies and births have occurred, and the group reported in Toronto in September at the American Society for Reproductive Medicine meeting that this results in heteroplasmy.
Definite diagnosis comes only after an autopsy of the deceased patient.
MRM uses a higher magnetic field, stronger magnetic-field gradients, and smaller radio frequency coils than magnetic resonance imaging. The plaques appeared as black, spherical objects. The researchers later stained the same tissue samples to view the plaques in the traditional manner. The group is now working on the challenges of in vivo imaging. Though use in humans is many years away, this technology could provide an invaluable tool in studying the early progression of neuritic plaques and Alzheimer's disease in animal models.