| Genetics of neurofibromatosis type 1 (NF1) | 866.000000000000 | Genetics of neurofibromatosis type 1 (NF1) | Genetics of neurofibromatosis type 1 (NF1) | G | English | Genetics | Child (0-12 years);Teen (13-18 years) | Eyes;Skin | Skin;Nerves | Conditions and diseases | Caregivers
Adult (19+) | NA | | 2010-03-05T05:00:00Z | | | | | | 6.30000000000000 | 73.8000000000000 | 768.000000000000 | | Health (A-Z) - Conditions | Health A-Z | <p>Neurofibromatosis Type 1 (NF1) occurs because of a mutation to the NF1 gene. About half of cases are spontaneous mutations, while the other half are inherited from a parent to a child.</p> | <h2>What is a gene?</h2>
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<span class="asset-image-title">What are genes?</span>
<img src="https://assets.aboutkidshealth.ca/akhassets/What_is_a_gene_MED_ILL_EN.jpg" alt="Cell, chromosome, DNA strand, gene and DNA building blocks or nucleotides" />
<figcaption class="asset-image-caption">Genes are made of long strings of nucleotides on a section of DNA. Groups of genes are packed tightly in a chromosome.</figcaption></figure>
<p>Our bodies are made up of billions of cells. The cells work together to make our bodies work. Different cells have different jobs, but they all have one thing in common: each contains genes. </p><p>Genes are the instructions that our cells use to make proteins. Genes tell our cells how to work and what to do. For example, one gene may determine the colour of your hair or your blood type. </p><p>Genes are packaged in the form of chromosomes. The information in a gene is coded in a chemical called DNA.</p><p>There are about 30,000 genes inside every cell. Each person carries two copies of each gene. A child gets (inherits) one copy from their mother and the other from their father.</p><p>For more information about genes, please see the AboutKidsHealth section on
<a href="/En/HowTheBodyWorks/GeneticsIntroduction" target="_blank">How the Body Works: Genetics.</a></p><h2>What causes NF1?</h2><p>Every person has two copies of the NF1 gene. This gene codes for a protein called neurofibromin (say: noor-oh-fie-BROH-min).</p><p>Neurofibromin's job in the body is to make sure that certain cells divide and grow in a controlled way. In particular, it stops certain cells that support the nerves from growing too much. These cells are called nerve sheath cells. </p><p>A mutation (a change in the genetic code) in the NF1 gene leads to a neurofibromin protein that does not work properly. This leads to symptoms of NF1. </p> | | <h2>Key points</h2>
<ul>
<li>A person can get NF1 in one of two ways. Half of cases happen completely by chance. The rest of the time, NF1 is inherited or passed down from parent to child.</li>
<li>In some cases, the signs or symptoms of NF1 are so mild that a parent may not find out they have NF1 until a child is diagnosed. </li>
<li>A person with NF1 has a 50% (one in two) chance to have an affected child with each pregnancy. </li>
<li>Adults may benefit from genetic counselling to understand their risks and choices regarding planning and family. </li>
</ul> | | | <h2>There are two ways to get NF1<br></h2><p>There are two ways a person can get NF1: as a new mutation, or by inheriting it from a parent.</p><h3>A new (spontaneous) mutation</h3><p>Half of all cases of NF1 occur by chance. This is called a new or spontaneous mutation. A change occurs in the NF1 gene at the time of, or shortly after, conception. Conception is the time when the father's sperm and the mother's egg join and the egg is fertilized. </p><p>In this case, neither parent of the affected child will have NF1. Spontaneous gene mutations are not inherited from either parent. </p><h3>Inherited from a parent with NF1</h3><p>The other half of people with NF1 inherited it from one of their parents. This means that a parent with a mutation in the NF1 gene passed the mutated gene to the child. </p><p>In some cases, the signs or symptoms of NF1 are so mild that a parent may not find out they have NF1 until their child is diagnosed. </p><h2>How NF1 is inherited</h2><p>Genes come in pairs, as do the chromosomes that carry them. When we have children, each parent passes half of their genetic material to their children, meaning one gene from each pair of genes. </p>
<figure class="asset-c-80">
<span class="asset-image-title">Heredity of neurofibromatosis (NF1)</span>
<img src="https://assets.aboutkidshealth.ca/akhassets/Neurofibromatosis_genetics_MED_ILL_EN.jpg" alt="Chromosome distribution from an affected parent with one chromosome with NF1 gene mutation an unaffected parent" />
<figcaption class="asset-image-caption">Every person has 2 copies of the NF1 gene, one on each chromosome. If a person has one mutated NF1 gene, he or she may develop the conditions of neurofibromatosis. An affected parent has a 50% chance of passing the mutated gene on to his or her child.</figcaption>
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<p>NF1 is inherited as a dominant condition. Dominant means the mutated gene is stronger than the normal gene. This means that only one NF1 gene needs to be mutated for the person to develop NF1. </p><p>If a person has NF1, they have one normal NF1 gene and one NF1 gene with a mutation. When this person has a child, they can pass on either the normal NF1 gene or the NF1 gene with the mutation. In other words, a person with NF1 has a 50% (one in two) chance of passing on NF1 to their children. </p><p>Adults with NF1 who are planning a family may wish to seek genetic counselling so that they can understand their risks and choices. </p> | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | https://assets.aboutkidshealth.ca/akhassets/What_is_a_gene_MED_ILL_EN.jpg | Genetics of neurofibromatosis type 1 (NF1) | | False | | | | | | |
