Did I REALLY Just Say That?! Trivia Quiz

Answer: spontaneous mutation

Almost half of all people with Nf1 or Nf2 are from a spontaneous mutation. Both are autosomal, defined as being one that is not a sex chromosome, and dominant, meaning that there needs to be only one mutated gene for the disorder to occur, as the faulty one cancels out the normal one.
The first time most people learn about either disorder is when they or a family member is diagnosed.

A spontaneous mutation of Nf1 occurs globally in 1 in 7000 births, for Nf2 it is 1 in 60000. When combined with inherited occurrences of the disorder that reduces it to 1 in 3000(Nf1) and 1 in 30000(Nf2).

Answer: Genes

Genes are the thousands of tiny pieces of information built on the chromosomes that make our DNA. They define our eye colour, natural hair colour, height and everything else that makes our physical selves us.

Humans have 23 pairs of chromosomes, twenty two pairs of which are autosomes and one pair of allosomes, making our sex/gender.

Sometimes the coding gets it wrong resulting in illnesses, disorders or inherited cancers that affect our health. In the case of Nf a fault is required on only one of the pair to occur.

Answer: nerves

Nf1 may cause neurofibromas(benign tumours) to grow on the peripheral nerves and nerve endings, while Nf2 causes bilateral Schwannomas (also benign tumours) in the balance and acoustic nerves as well as other cranial or spinal nerves. With both forms of Nf, the body doesn't produces the required proteins to stop growths and therefore the tumours will occur. The tumours are nearly always benign, though where they grow may cause other health problems.

There are three defined forms of dermal neurofibromas: cutaneous, sub-cutaneous and deep nodular. They may feel soft and spongy to touch, a bit like a marshmallow. Visually they may resemble a bubble or lump or a purplish discolouration on the skin. Most begin to appear in the teenage years and can continue throughout adulthood. Certain factors, such as pregnancy or hormonal changes, can influence their growth.

Sometimes people can develop larger, bulkier masses known as plexiform neurofibromas which grow along the nerve. Approximately ten percent of these may grow into a rare form of cancer known as Malignant Peripheral Nerve Sheath Tumours or MPNST.

Answer: cafe au lait

Birthmarks come in many forms and around ten percent of the population have one or two. Cafe au lait, or 'coffee with milk', coloured birthmarks are caused by overactive pigments in the skin cells. They are sometimes present at birth or begin to appear in the first few months. In people with Nf1 birthmarks can be numerous. Diagnostic criteria calls for six or more in a size greater than 5mm for children and 15mm for adults. Freckling often occurs in areas such as the armpit or groin. The number or size of birthmarks does not influence how severe other symptoms may be.

People with Nf2 may only have one or two or none at all. Unless there is a family history, it is not considered a diagnostic criterion.

Answer: Macrocephaly

Some people with Nf1 really do have big heads! While in most cases there aren't any major health symptoms from having an enlarged head, it does make finding a hat that fits difficult. There are sometimes cases where it can be a symptom of underlying disorders such as brain tumours or hydrocephalus. Macrocephaly can occur in those without Nf1 and is not a diagnosis criterion on its own.

While we are up here looking at the head another symptom of Nf1 can be lisch nodules, tiny brown marks on the iris. Lisch nodules have no impact on a person's vision.

Macrocephaly and Lisch nodules don't occur in Nf2.

Answer: scoliosis

Less than ten percent of people with Nf1 can also have skeletal problems such as scoliosis, though it may be used as a diagnostic criterion. Some of those who have scoliosis will require surgery or the wearing of a brace to correct the curvature. Any diagnosis would be monitored during regular check ups with a health professional or specialist.

Some people with Nf1 have a condition known as Psuedoarthrosis, where a false joint occurs in the bone. It is a rare symptom of the disorder and will require surgery to correct the bone or, in some cases, amputation.
Other bone problems that may occur include shortened, thinning, curved or even missing bones in the arm or the leg. Usually these are picked up in the first few years of life or soon after diagnosis. People with Nf1 are at a higher risk of osteoporosis later in life.

Answer: 50%

The chance of having further children with Nf would always remain the same at 1 in 2 (50%). The gender of previous children, and if they have Nf, does not affect any future children. Autosomal chromosomes are the twenty two other pairs that aren't sex chromosomes. A dominant disorder requires only one affected chromosome for occurrence, unlike a recessive disorder which requires a matching partner.

Unlike some disorders which may affect only one gender or certain ethnic groups, Nf doesn't discriminate. It occurs equally across the population worldwide with no preference for gender or race.

Answer: Nf1-17 and Nf2-22

Neuro what? Is the most common response when people first hear or see the name. The fault for Nf1 is on chromosome 17 and for Nf2 is on chromosome 22.
The gene to identify Nf1 was assigned in 1987 and was cloned in 1990 and the protein 'Neurofibromin' identified.

The gene to identify Nf2 was assigned in 1987 and was cloned in 1993 and the protein 'Merlin' identified.

Answer: Schwannomatosis

Schwannomatosis has not been studied as much as the two forms of Nf, though it has been identified as being located on chromosome 22, near where fault for Nf2 is. Unless there is a family history of Schwannomatosis diagnosis only occurs after Nf2 has been ruled out. Like Nf2 the tumours are made of Schwann cells, however do not grow on the vestibular nerve(the hallmark of Nf2). Tumours with Schwannomatosis don't grow on the skin and are unlikely to cause blindness or deafness, though the pain experienced from the tumours is greater than that experienced with Nf2. Cases of Schwannomatosis have a higher incidence of being from a spontaneous or sporadic mutation than the two forms of Nf with studies in the US estimating that may be as high as eight five percent. Its variability from person to person and within family units has made studying this disorder complex.

All these three disorders are variable from person to person. Some will have few symptoms, while others can have a lot. There is no way to predict what symptoms people may get or how severely they will be affected.

Answer: Medical professionals and official support websites

Google, your next door neighbour (unless they are familiar with the disorders) or old resource books are not the best option. Outdated, misinformation or worse case stories can cause distress for those new to the diagnosis. Some older resources have referred to Nf1 as the disorder that Joseph Merrick had but this has been proved incorrect.

While they both have near identical names Nf1 and Nf2 are two completely different disorders. Though both can cause benign tumours to grow on nerves, the part of the nerve they grow on is different; Nf1- Peripheral nerves and Nf2- Schwann cells.

Neurofibromatosis type 1 or Nf1 for short is the most common neurological disorder that is caused by a single gene, occurring in 1 in 3000 births world-wide. In the past it has been referred to as von Recklinghausen's disease and Peripheral Neurofibromatosis. Some medical professionals and texts books may refer to it by these names. Hallmarks of Nf1 are multiple cafe au lait birthmarks and non cancerous tumours growing on any of the body's nerves. Nf1 is extremely variable with its symptoms and not everyone will get them. In fact, you probably wouldn't find two people affected the same, even in the one family. After the physical symptoms of Nf1, the most common symptom is learning difficulties affecting half of all people. The incidence of a child with Nf1 having learning difficulties is five times higher than a child without. Learning difficulties may include problems with reading or writing, concentration, understanding mathematics, gross and or fine motor skills, behavioural problems, such as ADHD, and some may register on the Autism spectrum.

Neurofibromatosis type 2 or Nf2 for short is rarer, occurring in 1 in 30000 births. Hallmarks of Nf2 are bilateral benign tumours on the eighth cranial, affecting balance and may result in deafness. Tumours can also occur on the spinal nerves, cranial or optic nerves. Nf2 can be variable also, though the symptoms are more likely, as compared with Nf1, to cause life changing complications such as blindness or deafness. Unless there is a family history of Nf2, diagnosis doesn't usually occur until late teens or adulthood when hearing or vision becomes affected as there are fewer visual symptoms.

Unlike those with Nf1, most people with Nf2 will require surgery for their tumours. Nf2 has also referred to as Acoustic Nf or Central Nf.
It would be very unlikely for an individual to have more than one form of the Nf disorders. One form can't develop into another.

Over two million people worldwide have a form of Nf and yet most people have never heard of it. May is world Neurofibromatosis awareness month, with 17th May the awareness day.

Now you have learned a bit about neurofibromatosis and learned how to pronounce it, wipe your brow and give yourself a pat on the back and say "Did I REALLY just say that?"