Ehlers Danlos Syndrome - an inherited connective tissue disorder that might cause hyperlordosis, which means that the natural curve of the lumbar region of the back gets dramatically accentuated.

Siamese twins - a rare disorder in which twins are born joined together at one or more parts of their bodies.

Hypertrichosis - a disorder that causes abnormal amount of hair growth over the body. This is a very rare disease, and only 40 humans are known to suffer from it at present.

Fused limbs - One in every 70,000 babies has this disorder.

Cyclopia - children born with this awful disfiguration have one eye in the middle of their head. It looks gruesome, so here's a picture of Leela from Futurama, instead. If you still want to know how it looks like in reality, go ahead and google the term and click on image search. You have been warned.

Craniopagus parasiticus - a condition in which a child is born with a parasitic extra head from their unborn twin.

Fibrodysplasia ossificans progressiva - hildren who are born with this disease grow bone in areas that are hurt, instead of scar tissue.

Progeria - Causes a child to look aged well beyond their years. It occurs in one in eight million births.

Vestigial tail - when a child is born with a semi-functional tail, with muscles, nerves, skin, and blood vessels.