Power, Sex, Suicide: Mitochondria and the Meaning of Life (69 page)

¹
Sharp readers may notice a dilemma here, which has been articulated by Ian Ross, at UC Santa Barbara. The mitochondria are adapted to the
unfertilized
oocyte nuclear background, but this changes when the oocyte is fertilized and the father’s genes are added to the mix. If the adaptation of mitochondria to nuclear genes is not to be lost, then the maternal nuclear genes should overrule the paternal genes—a process known as imprinting. Many genes are maternally imprinted but whether some of these encode mitochondrial proteins is unknown. Ross predicts they will be, and is studying mitochondrial imprinting in a fungal model.

¹
The longest recorded human life was Jeanne Calment, who died in 1997 at the age of 122. Without an heir at the age of 90, she signed a deal with a lawyer in 1965, who agreed to pay an annual retainer for her apartment, which he would inherit upon her death. The full value would be paid in 10 years. Unfortunately, the lawyer himself passed away in 1995, after 30 years of payment, and his wife had to continue paying after his death.

¹
The status quo is also linked with tissue oxygen concentration. In
Part 4
, we noted that tissue oxygen levels are poised at 3 or 4 kilopascals across the entire animal kingdom. This means that both oxygen levels and antioxidant levels are balanced in the cell to retain a roughly constant redox state. We’ll see why later in
Part 7
.

²
Mendel’s laws govern the pattern of inheritance of ‘normal’ nuclear genes, in which the likelihood of a genetic trait or disease can be calculated according to the probability that an individual will inherit at random one of two copies of the same gene from each parent, giving everyone two copies of each gene. In fact, some mitochondrial diseases do follow Mendel’s laws, as they are caused by nuclear genes encoding proteins destined for the mitochondria.