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The Rarest And Most Gruesome Genetic Diseases Known To Science

Updated March 14, 2019 682.5k views13 items

The genetic lottery can deal out some pretty harsh prizes and some people are dealt horrible hands completely at random. Your genes have a crazy amount of control over your life - and having a couple go haywire can cause some of the most bizarre and horrifying effects known to man. Weird genetic traits and rare diseases may not be common, but the side effects can be so gruesome that they become infamous after a single case. 

Uncommon genetic disorders can happen to anyone, even with all of the amazing wonders that modern medicine can perform. Some of the worst sicknesses to have are ones that can't be cured, and those are often the scariest diseases. Scientists have done a lot of research into what makes these atrocious abnormalities arise in otherwise healthy humans, but there are still some illusive diseases that science can't explain. Read on to discover some of the rarest, deadliest, and most gruesome genetic diseases and conditions that have ever afflicted humankind. 

  • Almost exclusively affecting men, Lesch-Nyhan syndrome is caused by a buildup of uric acid in the body. The lack of an enzyme caused by a malfunctioning HPRT1 gene means that the body can't properly recycle purine, one of the building blocks of DNA. People suffering from this disease experience a severe lack of motor functions, gout-like symptoms, kidney stones, and self-mutilation.

    The afflicted are often known to bite off their fingernails or try to chew through their own lips. Involuntary spasms and muscle contractions are common and cannot be treated, although there are some medications that can lower uric acid levels and reduce other symptoms.

  • Photo: NASA Johnson Space Center / Wikimedia Commons

    This disorder is characterized by the total or near-total lack of any sort of immune system, making patients susceptible to every sort of pathogen under the sun. Defective white blood cells are the root cause of this disorder, making life exceedingly difficult. Many sufferers perish before their first birthday, but new procedures are increasing the chance of a healthy life for many.

    It is known as the "bubble boy" disease because of the extensive environmental sterilization needed to prevent recurring infections. A young boy named David Vetter was possibly the most famous example of someone living with SCI, as he was able to survive until the age of 12 with the help of his "bubble" environments.

  • Cystic fibrosis was once a terminal sentence for young children, but modern medicine has allowed sufferers of this ailment to live much longer lives. A defect of the CFTR gene makes it so that cells are unable to produce mucus properly. The flawed mucus is much thicker than it is supposed to be, causing all sorts of buildup and blockages throughout the body.

    The intestines, pancreas, and especially the lungs are all affected by this disease. Mucus-filled lungs lead to shortness of breath, constant infections, and permanent scarring. Digestive issues are extremely common for those with cystic fibrosis. In addition, men are often sterile due to mucus blocking their reproductive tracts.

  • Parkinson's is not an exceedingly rare disease, as roughly one million Americans are currently living with the diagnosis, but it is a very serious threat. It's a progressive disease, meaning that the symptoms will only get worse over time. People suffering from Parkinson's disease often first notice minor tremors in their limbs, but this is just the tip of the iceberg.

    Parkinson's is brought on by the degradation of important brain cells which trigger a range of physical disabilities. Over time, near total loss of muscle control can occur. It is not clear what exactly causes this disease, but it is believed to have a genetic component. Other symptoms include dementia, hallucinations, and depression. There is no cure for Parkinson's, but treatment can reduce some of the symptoms.

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