This transmission would probably require ingestion of prion-affected brain tissue itself, but other prion diseases have also been theorized to transmit very rarely during medical procedures like blood transfusion or organ transplants as the prions can be found in other bodily tissues at very low levels. In theory, FFI might also be transmissible. Most often, this occurs through familial genetic inheritance, but extremely rarely it can occur in other individuals through random genetic mutation. They actually make the prion themselves due to the faulty genetic code. In the case of FFI, which is a genetic condition, patients don’t acquire the misfolded protein from another source. Kuru, another prion disease found in certain tribes in New Guinea, continued its transmission through human populations by the ritual funeral ingestion of deceased prion carriers’ brains. Similarly to FFI, there has sadly never been a human survivor of this type of prion disease. While “mad cow disease” circulated among, well, cows, outbreaks of another disease – variant Creutzfeldt-Jakob Disease – appeared in humans and is thought to have occurred from humans ingesting the meat from prion-producing cows. Ingestion or injection of the misfolded protein can cause the misfolding of proteins in another host.
You may have heard of prion diseases in the news if you’ve ever paid attention to outbreaks of “mad cow disease.” Yes, prion diseases are actually transmissible.
The structure of the prion protein, which is encoded by the PRNP gene This not only makes the proteins unable to proceed with their usual roles, but can also cause them to stick to each other in clumps. Although it’s not understood how this happens, the misfolded prion protein can induce other proteins to take on an inappropriate shape. Certain genetic mutations, such as the one that causes FFI, disrupt the ability of that protein to take on the correct shape. The ability of proteins to do their jobs in our body relies heavily on their structure – after a genetic sequence is translated into protein building blocks, these building blocks must fold into the correct shape.
FATAL INSOMNIA CODE
Prion diseases are caused by a mutation in the genetic code for a specific protein called the prion protein, which causes it to misfold. So, how does a genetic defect and its effect on the brain cause these devastating effects? What can we learn about the reciprocal relationship between sleep and the brain? And is there any hope for treatment?įFI is known as a prion disease. This dysregulation leads to rapid heart rate, sweating, pupil dilation, and inability to regulate body temperature. Other hallmarks of the disease follow from dysregulation of the autonomic nervous system, which is made up of the nerves that control involuntary bodily functions. Physically, FFI patients may experience trouble with the coordination of movement, tremors, muscle spasms, and difficulty moving their eyes and swallowing. Psychological effects include confusion, dementia, hallucinations, and issues with memory and language. In addition to mild insomnia that subsequently develops into the total inability to fall asleep, patients typically experience other mental and physical symptoms as the disease progresses. Therefore, children have a 50% chance of inheriting the disorder when one of their parents carries the mutation. It is inherited through family genetics in an autosomal dominant manner, meaning just one mutated copy of the two PRNP genes – one inherited from each parent – leads to disease. FFI is caused by a mutation in a gene called PRNP, which encodes a protein called prion protein (more on this later). To assuage the fears of any insomniacs reading this article, cases of FFI are extremely rare, with only 70 total families worldwide ever reported in the scientific literature to pass down the genetic defect. Sadly, the disease is always fatal and follows an accelerated course of degeneration – by the time patients begin to show insomnia symptoms and are diagnosed in their 40s, 50s, or 60s, FFI only takes an average of 18 months to cause death. What if you were, however, gradually unable to fall asleep? In very rare cases of people with fatal familial insomnia (FFI), this is exactly the outcome of their genetically-driven neurodegenerative disease.įFI is a genetically-acquired disease which is, as the name suggests, marked by the inability to fall asleep. The role of sleep in our everyday health is critical, which is no more apparent than the day after one of those sleepless nights when we might feel grumpy, forgetful, or ill. No matter how tired we are, we all have nights when we just can’t fall or stay asleep. Not being able to fall asleep when you want to is frustrating.