Question: Is optic atrophy ginetic and what cause it?

Reference:
 Optic atrophy 1 OPA1 Optic atrophy, juvenile Kjer-type optic atrophy OPA1 Optic atrophy, juvenile Kjer-type optic atrophy Optic atrophy, Kjer type OAK Optic atrophy type 1 Autosomal dominant optic atrophy, classic form See More Summary Optic atrophy 1, also known as optic atrophy type 1 is a disease that affects the optic nerve. The optic nerve carries signals from the eye to the brain about what is seen. People with optic atrophy type 1 have an optic nerve that has lost some tissue ( atrophy). This atrophy causes the optic nerve not to work as well as it should, which affects the vision. Signs and symptoms of optic atrophy type 1 include vision loss, difficulty distinguishing colors, and an abnormally pale appearance (pallor) of the optic nerve. The vision loss typically begins at age 4-6 years-old. The disease can occur in people of any ethnicity but seems to be more common in people of Danish descent. [1] Other symptoms of optic atrophy type 1 may include sensorineural hearing loss , difficulty coordinating movements ( ataxia ) and muscle disease ( myopathy). When people have optic atrophy type 1 and signs and symptoms other than vision loss, it is known as autosomal dominant optic atrophy plus syndrome. [1] Optic atrophy type 1 is caused by a genetic change (pathogenic variant or mutation ) in the OPA1 gene . The disease is inherited in an autosomal dominant manner. Optic atrophy type 1 may be suspected when a person has signs and symptoms of the disease on an exam done by an ophthalmologist . Genetic testing may be used to confirm the diagnosis. Treatment for optic atrophy type 1 may include vision and hearing aids when necessary. [1] [2] Symptoms The signs and symptoms of optic atrophy type 1 include changes in vision. People with the disease typically have vision loss that begins between 4-6 years-old. The vision loss typically affects both eyes and can cause a person to have a range of vision loss from mild to being legally blind. People with optic atrophy type 1 may experience narrowing of the visual field (tunnel vision). [1] [2] Vision loss may worsen as people with the disease get older. Optic atrophy type 1 can also cause a change in color vision, making it difficult to distinguish between blue and yellow colors (tritanopia). [1] Other signs and symptoms of optic atrophy type 1 may affect other parts of the body. People who have signs and symptoms other than vision loss have autosomal dominant optic atrophy plus syndrome. Some people with the disease may have hearing loss that is caused by damage to the nerves in the ears ( sensorineural hearing loss ). In severe cases, the hearing loss may be present from birth ( congenital ), but in other cases it may not be noticeable until a person undergoes a hearing evaluation. Other signs and symptoms of the disease may include difficulty coordinating movements ( ataxia ) and muscle disease ( myopathy). [1] The signs and symptoms of optic atrophy type 1 can vary widely, even among people in the same family. For example, some people may have severe vision loss, hearing loss, and muscle weakness, while other people may only have mild vision loss. This wide variation of signs and symptoms of the disease is called variable expressivity . In some cases, people with a genetic change (pathogenic variant or mutation ) in the OPA1 gene may not have any signs of optic atrophy type 1 at all. This is called reduced penetrance . [1] [2] This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom. Showing of Medical Terms Other Names Learn More: HPO ID 1%-4% of people have these symptoms Ataxia 0001251 Horizontal nystagmus 0000666 Progressive external ophthalmoplegia 0000590 Proximal muscle weakness Weakness in muscles of upper arms and upper legs 0003701 Strabismus Cross-eyed Squint Squint eyes 0000486 Percent of people who have these symptoms is not available through HPO Abnormal amplitude of pattern reversal visual evoked potentials 0000650 Autosomal dominant inheritance 0000006 Central scotoma Central blind spot 0000603 Centrocecal scotoma 0000576 Incomplete penetrance 0003829 Insidious onset Gradual onset 0003587 Optic atrophy 0000648 Pallor 0000980 Red-green dyschromatopsia Red green color blindness 0000642 Reduced visual acuity Decreased clarity of vision 0007663 Tritanomaly Blue yellow color blindness 0000552 Showing of Cause Optic atrophy type 1 is caused by a change (pathogenic variant or mutation ) in the OPA1 gene . This gene provides instructions to the body to make a protein that helps the mitochondria function correctly. Mitochondria are the parts of the cell that help the cell produce energy. The protein that is created by the OPA1 gene helps the mitochondria maintain a normal shape and structure. Therefore, this protein is important in helping mitochondria create energy for the cells to use. The protein also has a role in the process called programmed cell death ( apoptosis ). [2] When there is a pathogenic variant in the OPA1 gene, there is not enough functioning protein to help the mitochondria maintain the normal shape and structure. This causes the mitochondria to not produce enough energy for cells. It also causes cells to undergo cell death earlier than they should. When cells of the eyes do not receive enough energy and undergo cell death earlier than they should, it causes loss of tissue in parts of the eye called the retina and the optic nerve. These parts of the eye transmit signals from the eyes to the brain so that we can see. Loss of cells in the retina and optic nerve cause the signs and symptoms of optic atrophy type 1. [2] In some cases, people with optic atrophy type 1 do not have a pathogenic variant in the OPA1 gene that is found on genetic testing . In these cases, the exact cause of the disease is unknown. [3] Inheritance Optic atrophy type 1 is inherited in an autosomal dominant manner. [1] This means that having a genetic change (pathogenic variant or mutation ) in one copy of the OPA1 gene can cause the signs and symptoms of optic atrophy type 1. We inherit one copy of the OPA1 gene from our mother and the other from our father. When a person with a pathogenic variant in OPA1 has children, for each child there is a: 50% chance to inherit the changed copy of OPA1 50% chance to inherit the working copy of OPA1 When a person has a pathogenic variant in the OPA1 gene, it can be difficult to predict the signs and symptoms that the person may have. This is because the signs and symptoms of optic atrophy type 1 can vary, even among members of the same family ( variable expressivity ). In addition, some people with pathogenic variants in OPA1 do not have any signs or symptoms of optic atrophy type 1 at all ( reduced penetrance ). [1] In most cases, people with optic atrophy type 1 inherit the pathogenic variant in OPA1 from one of their parents. This parent may have different signs and symptoms of the disease than other family members, or the parent may not have any signs or symptoms of the disease at all. [1] It is not known why there is such a wide variation of signs and symptoms that can be associated with optic atrophy type 1. It may be that there are genetic and environmental factors that influence the signs and symptoms of the disease. [4] In some cases, a pathogenic variant in the OPA1 gene occurs for the first time in the person diagnosed with optic atrophy type 1, and it was not inherited from either parent. Pathogenic variants that are occurring for the first time are called de novo . [1] People who have questions about the chances for other family members to have optic atrophy type 1 may wish to speak with a genetic counselor . Diagnosis Optic atrophy type 1 may be suspected when a person has signs and symptoms of the disease including vision loss beginning in childhood, loss of color vision affecting blue and yellow colors (tritanopia), and findings of loss of tissue of the optic nerve ( optic atrophy) on an exam by an ophthalmologist . A doctor may take a medical history and family history , as people with optic atrophy type 1 may have other signs and symptoms of the disease or other family members with signs and symptoms. The diagnosis can be confirmed with genetic testing of the OPA1 gene . [1] Treatment Treatment for optic atrophy type 1 typically includes regular exams by an ophthalmologist , including measuring vision and color vision, and regular evaluation by an audiologist . Vision aids such as glasses, contact lenses, and magnifiers may be used to help treat vision loss. Cochlear implants may help improve hearing in people who have sensorineural hearing loss . [1] Some people with optic atrophy type 1 have shown improvement in vision after being treated with idebenone. However, more research is needed to determine how effective this medication is in treating the disease. [3] [5] People with optic atrophy type 1 may be recommended to avoid alcohol intake and certain medications, as these can impact the function of mitochondria in the cells . [1] Prognosis In general, people with optic atrophy type 1 have worsening vision loss over time. However, some people only have mild vision loss, and for some people the vision loss does not worsen with time. Vision loss can interfere with daily life, but it is not expected to shorten a person's lifespan. [4] The long-term outlook for people with optic atrophy type 1 may depend on the severity of vision loss and if there are any other symptoms, such as hearing loss or muscle weakness. About 20% of people with a genetic change (pathogenic variant or mutation ) in the OPA1 gene have symptoms other than vision loss. [4] In some cases, people with optic atrophy type 1 may experience anxiety and depression due to the symptoms of the disease. [4] It is important to contact your doctor if you have concerns that you or a family member is suffering from anxiety or depression. Find a Specialist If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments. If you can't find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care. You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists. Healthcare Resources To find a medical professional who specializes in genetics, you can ask your doctor for a referral or you can search for one yourself. Online directories are provided by the American College of Medical Genetics and the National Society of Genetic Counselors. If you need additional help, contact a GARD Information Specialist. You can also learn more about genetic consultations from Genetics Home Reference. Related Diseases Related diseases are conditions that have similar signs and symptoms. A health care provider may consider these conditions in the table below when making a diagnosis. Please note that the table may not include all the possible conditions related to this disease. Conditions with similar signs and symptoms from Orphanet Differential diagnosis includes all the common causes of optic neuropathies: compressive, inflammatory, ischemic, toxic and metabolic causes. Other hereditary optic neuropathies such as leber hereditary optic neuropathy, Wolfram syndrome (see these terms) have different initial presentations (later in life, associated or not with other neurological or systemic signs), but the final clinical phenotype of optic neuropathy is not specific. Visit the Orphanet disease page for more information. 

Answer: Optic atrophy 1 is usually caused by  mutations in the OPA1 gene , although some individuals with optic atrophy 1 do not have identified mutations in this gene, in which case the cause of the condition is unknown. This condition is inherited in an  autosomal dominant pattern but some cases result from a new mutation in the gene and occur in people with no history of the disorder in their family.