Immortal

At its core, age is believed to be caused by seven factors. As of the 21st century, many aspects of these problems are already solved, though research proceeds with caution, and is hampered by many illegitimate products and promotions.

The first to be discovered, in 1907, is the accumulation of extracellular junk that the body has no particular means of digesting or getting rid of. The main culprit here is a fibrous protein called amyloid, which builds up in plaques and is suspected to cause Alzheimer's disease. The natural solution at this point seems to be to convince the proper cells to consume amyloid, and deal with it as intracellular junk. This accumulation of junk also causes atherosclerosis, although the body already attempts to solve this, it has little real effect, as it also functions as intracellular junk, below.

Cell loss and atrophy is probably the best 'solved' of the problems. The simple problem is that not all cells replicate themselves fully or properly, particularly in the heart and brain, and thus need replacement. Stem cell research, artificial stimulation, and natural stimulation (via a little-known process called exercise), provide a solid set of complementary solutions.

Intracellular junk is the slow, but inevitible accumulation of molecules that the cells of the human body have no means of breaking down, eventually causing the cells to stop functioning. This causes a wide variety of age-related diseases, including atherosclerosis above, but also degrades vision and causes a gradual loss of motor control. Although human cells cannot break these down, it is known that bacterial and/or fungal cells do, and genetic study and therapy is being considered as a possible solution.

The fourth is called mutation, which sometimes results in cancer. Books could be written about the progress achieved in the past half-decade alone, on several levels.

Cell senesence - the accumulation of unwanted cells, is possibly the simplest of them, though among the least researched. The most common example of this is the development of insulin resistance due to the accumulation of abdominal fat cells, often seen as a factor in hereditary diabetes, although it is becoming somewhat apparent that everyone faces this risk eventually.

Extracellular crosslinking is the eventual bonding of long-lived proteins that the body does not normally replace. This causes a number of problems, including the hardening of artery walls, and thus high blood pressure. There is already at least one drug in trials that breaks some of these crosslinks down, though it is not a complete solution.

The final issue is mitochondrial mutations. As mitochondria have their own DNA, even if not much of it is used (a lot of work has been overtaken by the host cell), it must still be addressed. While solutions have been proposed, things are proving somewhat difficult in this area.

Another factor in the following is that many diseases - bacterial, viral, and other, have many specifc, limited routes into the cell structure of the body. Several potential panaceas have already been hypothesized, leaving humanity with a scant few risks to individual health, mostly of its own causing.

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The end of the 21st century saw the first truly modified humans, people artfully adjusting their own genetics to various ends. Although a great deal of research had made this viable by the middle of the century, protests and laws hindered the inevitible for some decades.

This did not often occur under benign circumstances, or for moral reasons. Thousands died in experiments, though in many cases it was an intentional slip up by one or more scientists to eradicate a hopelessly corrupt benefactor. As intelligent people tend to go, they weren't often caught.

To say that the populace of Earth had concerns is an understatement. Earth's closest brink with global war was not between nations, or even religions, but between classes. No amount of censorship could supress the rumor.

"Immortality is on our doorstep, and they would hold it from us."

The Prometheus Accords were born.