12 Rarest Medical Conditions The World Has Ever Seen

It’s mind-boggling how much luck goes into creating a healthy human being. 

With only a slight mutation of a very small strand of genetic information, your body can work in a totally different way. Sometimes you can judge how your body and mind will end up based on what you observe from the rest of your family, but it’s also possible for a condition to quietly pass through your family genes before some slight change in your DNA brought it to the forefront.

Most people won’t have even heard of some of the conditions on this list, but the rare few who have them live with their extreme effects every day.

It can definitely be said that these 12 rare medical realities will make life interesting — but not in a way that most of us would want.

1. Cotard’s Syndrome

In the most extreme cases, this sad mental disorder leads its sufferers to believe that they are dead.Those afflicted with this variation of the disease will often feel compelled to visit cemeteries and morgues for the purpose of joining their “fellow” dead people. Cotard’s syndrome is often linked with intense feelings of depression and paranoia, as being alive will feel unnatural to those afflicted with it.

A man named Per “Dead” Ohlin of the black metal band Mayhem was suspected to suffer from Cotard’s syndrome, as he often expressed his belief that he was already dead and was reported to keep a dead crow around so he could sing with “death in his nostrils.”

2. Nystagmus

Sometimes called, “dancing eyes,” this brain disorder impairs the functions of the labyrinth, a part of the inner ear that helps control eye movements. As a result, those afflicted with nystagmus will experience rapid, uncontrollable eye movements. Nystagmus is often congenital, or present at birth, but it can also develop from the use of an anti-seizure medication called Phenytoin, as well as from severe head injuries, strokes, and inner ear disorders.

3. Oligodactyly

Those afflicted with this condition are born with less than five fingers on each hand. The remaining fingers can be perfectly functional, but vary in number depending on the severity of the condition. It’s usually heredity, but can also be associated with other diseases like Roberts syndrome in cases where there’s no family history of oligodactyly.

4. Polydactyly

As opposed to oligodactyly, this condition finds its sufferers born with extra fingers or toes. 1 in 1,000 babies are born with some degree of polydactyly, but it’s rarer for the extra digits to be fully formed and functional.Like oligodactyly, it’s an inherited condition, but it usually only manifests in one member of a family.