Polyrrhinia is an extremely rare condition present at birth where a baby develops two noses instead of one. In plain terms, polyrrhinia affects the structure of the face, and early signs of polyrrhinia are usually obvious at birth or on prenatal imaging. Some babies with polyrrhinia also have other differences in the nose, brain, or face, so the outlook can vary. Treatment usually involves care from a specialist team, and surgery may help with breathing, feeding, and appearance. Because polyrrhinia can occur with other serious birth differences, the risk to life depends on how severe those related problems are.
How many people live with Polyrrhinia?
Polyrrhinia is so rare that no reliable worldwide estimate is available, and no single authoritative source consistently reports how many people are living with it globally. The same is true in the United States: there is no dependable national estimate, and published information is limited mostly to individual case reports rather than a full count.
Overview
PolyrrhiniaSymptoms
Polyrrhinia is an extremely rare condition where a baby is born with two noses or a partly duplicated nose. Features are usually noticed at birth. Some babies also have breathing, feeding, or other facial differences.
Outlook and prognosis
For people with polyrrhinia, outlook depends mostly on whether there are other facial or brain differences, not just the extra nasal tissue itself. Many living with polyrrhinia can do well after staged reconstructive surgery, but feeding, breathing, and development may need close follow-up.
Causes and risk factors
Polyrrhinia usually arises before birth from a very early developmental error, often without a known cause. It is usually not inherited. No lifestyle or environmental risk factors are clearly established.
Genetic influences
Genetics may play a role in Polyrrhinia, but the exact cause is still unclear because so few cases have been reported. Many cases seem sporadic, though changes affecting early facial development could contribute in some people with Polyrrhinia.
Diagnosis
Polyrrhinia is usually diagnosed at birth from clinical features, especially an extra or split nose, and doctors often use imaging to check nearby facial structures. Genetic tests may help confirm the diagnosis of polyrrhinia and look for related conditions.
Treatment and drugs
Polyrrhinia is usually treated with surgery, often in stages, to improve breathing, feeding, and facial structure. Care is planned by craniofacial, ENT, and anesthesia teams, with scans guiding timing. Some children also need treatment for related clefting or brain differences.
Symptoms
Breathing, feeding, and the shape of the middle of the face can all be affected from birth. For many people with polyrrhinia, the main signs are visible right away, although the effect on breathing or feeding can range from mild to more serious. Some babies also have nearby facial differences, so doctors usually look carefully for related findings.
The most noticeable sign is an extra nostril or a partly or fully duplicated nose. The early features of polyrrhinia are often obvious at birth, though some are first suspected on prenatal imaging.
Extra nasal tissue or narrow passages can make it harder for air to move through the nose. In a newborn, this may show up as noisy breathing, flaring nostrils, or trouble breathing while feeding or sleeping.
If breathing is difficult or the roof of the mouth is affected, feeding can take more time and effort. Some babies tire easily during feeds or struggle to latch and suck well.
Some babies with polyrrhinia also have a broad nasal bridge, wide-set eyes, or a cleft lip or palate. These differences can affect appearance and sometimes speech, hearing, or dental development later on.
How people usually first notice Polyrrhinia?
Polyrrhinia is usually first noticed at birth, because the baby is born with an unusually formed nose that may appear partly duplicated or, in very rare cases, split into two nose-like structures. The first signs of polyrrhinia can also include trouble with breathing, feeding, or airflow through the nose, which often leads doctors to examine the face and nasal passages closely soon after delivery. In some pregnancies, how polyrrhinia is first noticed may be on prenatal ultrasound, but for many families it becomes clear right away when the baby is born and the facial difference is seen during the first newborn exam.
Types of Polyrrhinia
No distinct types of Polyrrhinia are widely recognized.
Can I slow down the onset of symptoms?
No. Polyrrhinia is an extremely rare difference in how the nose forms before birth, so it does not have a later onset that lifestyle changes or medical treatment can meaningfully slow down, and there is no proven way to reduce the risk of it happening or to prevent it. Care is aimed instead at early evaluation and, when needed, surgery or other support to help with breathing, feeding, and day-to-day function, and while that cannot change when the condition begins, it can still make a real difference in comfort and quality of life.
What genetics can tell you about symptoms
For people living with polyrrhinia, genetics can sometimes help explain why the condition happened, but it usually cannot predict day-to-day symptoms very well because this is an extremely rare condition. In the small number of reported cases, differences in early facial development genes may play a role, yet there is no well-established genetic pattern that reliably tells doctors which symptoms will appear, how severe they will be, or exactly when related breathing, feeding, or facial differences will be noticed. In practice, symptoms and their impact are judged mainly from the individual’s anatomy and any associated differences in the face, brain, or airways rather than from genetic testing alone.
Causes and risk factors
Polyrrhinia usually begins very early in pregnancy, when the tissues that form the nose develop in an unusual way. The exact causes of polyrrhinia are still not clear, but most cases seem to happen sporadically rather than being passed down in families. Some reported cases occur with other birth differences, which suggests that new genetic changes or other early developmental changes may play a role. Having a gene change doesn’t mean you’ll definitely develop the condition. No specific lifestyle or environmental risk factors for polyrrhinia have been proven, and it is not thought to be caused by anything a parent did or did not do.
What are the most common causes or risk factors?
Polyrrhinia is an extremely rare birth difference where the nose starts to form in an unusual way very early in pregnancy, leading to a partly or fully duplicated nose. In most reported cases, the exact cause is unknown, but it can happen along with other changes in how the face and head develop, and in a few people there may be an underlying genetic or chromosome change. Because it is so rare, there are no clearly proven everyday risk factors such as diet, activity, or common exposures, and most cases do not seem to be passed down in families.
Environmental and biological risk factors
Polyrrhinia is so rare that the known risk factors for polyrrhinia are still not well defined. It appears to begin very early in fetal development, when the tissues that form the nose and center of the face are being laid out. That said, biology and environment work hand in hand, and a few factors are known to raise the chance of craniofacial birth differences in general even though they have not been proven causes of polyrrhinia.
No single environmental or biological factor has been confirmed as a clear cause of polyrrhinia. In many reported cases, there is no obvious explanation during pregnancy.
Polyrrhinia is thought to start in the first weeks of pregnancy, when the tissues that form the nose and middle of the face are developing. A disruption during this stage may increase the chance of the condition, although the trigger is usually unclear.
Doctors believe polyrrhinia is linked to an early disturbance in how the center of the face is patterned before birth. This points to a biological problem in development rather than something that happens later in pregnancy.
Poorly controlled diabetes in early pregnancy is a recognized biological risk for several birth differences, including some that affect the face. It has not been proven to cause polyrrhinia, but it may be considered a possible contributing factor.
Genetic risk factors
For families facing a diagnosis of polyrrhinia, one of the first questions is whether it was inherited. In most reported cases, polyrrhinia appears to happen sporadically, meaning there is no known family history and no single proven inherited cause. The genetic causes of polyrrhinia are still not fully understood, in part because the condition is extremely rare. In some cases, genetic testing can give a clearer picture of your personal risk.
Sporadic occurrence: Most cases of polyrrhinia seem to happen as isolated events rather than being passed down through a family. This suggests that many people with polyrrhinia are the first in their family to be affected.
New genetic changes: Some researchers think a new genetic change arising very early in development may play a role in certain cases. This is called a de novo change, and it means the change was not clearly inherited from a parent.
Chromosome differences: In a small number of cases, polyrrhinia has been reported along with larger chromosome changes or other genetic differences. When this happens, the extra nasal tissue may be one part of a broader pattern of differences present from birth.
Developmental genes: Genes that help shape the middle of the face before birth are considered possible contributors, because polyrrhinia affects structures that form very early in pregnancy. Even so, no single gene has been confirmed as the usual cause.
Inheritance pattern: There is no well-established inheritance pattern for polyrrhinia, such as a clear dominant or recessive form. Because of that, the chance of it happening again in a family is often uncertain and may depend on whether a specific genetic change is found.
Syndromic cases: Some people with polyrrhinia also have other differences involving the brain, eyes, or facial bones. In these situations, doctors may look more closely for an underlying genetic syndrome or chromosome condition.
Lifestyle risk factors
Polyrrhinia is a very rare congenital facial difference, so lifestyle habits do not cause it. Still, how lifestyle affects polyrrhinia can matter for breathing comfort, feeding, recovery after treatment, and the risk of complications. In practice, lifestyle risk factors for polyrrhinia are the day-to-day factors that can worsen airway irritation, infection risk, nutrition problems, or overall resilience.
Smoking and secondhand smoke can irritate the nasal passages and airways, which may worsen congestion, breathing difficulty, or crusting in someone with polyrrhinia. Avoiding smoke may help reduce inflammation and support healing, especially before or after surgery.
Poor nasal hygiene or frequent forceful manipulation can increase irritation, bleeding, or local infection around abnormal nasal structures. Gentle cleaning and following specialist advice may improve comfort and lower complication risk.
In people with polyrrhinia who have feeding difficulty or repeated surgeries, inadequate calorie and protein intake can slow growth and delay wound healing. Good nutrition supports recovery, immune function, and overall strength.
Physical activity does not cause or prevent polyrrhinia, but exercise tolerance may be affected if nasal airflow is limited. Choosing activity levels that match breathing capacity can help maintain fitness without excessive respiratory strain.
Risk prevention
Polyrrhinia is a very rare birth difference in which extra nasal structures develop before birth. In most cases, there is no known action that can fully prevent polyrrhinia, because it forms very early in pregnancy and often happens sporadically. Prevention usually focuses on lowering the chance of birth differences in general and, if polyrrhinia is diagnosed, reducing complications through specialist care. Prevention is about lowering risk, not eliminating it completely.
Seeing a doctor before pregnancy can help review medicines, medical conditions, and exposures that may affect early fetal development. This is useful because polyrrhinia begins forming in the first weeks of pregnancy, often before someone knows they are pregnant.
Taking folic acid before conception and in early pregnancy helps support normal development of the baby's face, brain, and spine. It cannot specifically prevent polyrrhinia, but it is a standard step to lower the risk of some major birth differences overall.
Limiting alcohol, avoiding smoking and recreational drugs, and checking workplace or home chemical exposures may reduce risks to early development. Ask about prescription and over-the-counter medicines too, since some are safer than others during pregnancy.
Good control of diabetes and other long-term health problems before and during pregnancy supports healthier fetal development. Regular prenatal care can also help catch concerns early and lower the chance of avoidable complications.
Can you prevent Polyrrhinia?
No, there is no known way to prevent polyrrhinia. It is an extremely rare condition that develops very early before birth, and in most cases the exact cause is not known, so it is usually not linked to anything parents did or did not do. Regular prenatal care is still important for overall pregnancy health, but it cannot be relied on to prevent this condition.
Transmission
Polyrrhinia is not infectious, so it cannot be caught from another person through the air, touch, blood, sex, food, or everyday contact. It is a very rare condition that develops before birth, and the genetic transmission of Polyrrhinia has not been clearly shown in families.
Because only a small number of cases have been reported, how Polyrrhinia is inherited is still not fully understood, but many cases seem to happen as a new change very early in development in the womb rather than being passed down from a parent. If a baby is born with Polyrrhinia, a genetics specialist can help review family history and discuss whether testing may clarify the chance of it happening again.
When to test your genes
Because polyrrhinia is usually visible at birth, genetic testing is most useful when it appears alongside other birth differences, developmental concerns, or a family history of craniofacial conditions. In that setting, testing can help look for an underlying syndrome and guide imaging, specialist care, and family counseling.
Diagnosis
Polyrrhinia is usually diagnosed at birth because the facial differences are visible right away, and doctors then use imaging and other exams to understand how the nose and nearby structures formed. In some families, the condition is first suspected before birth on routine prenatal imaging. Getting a diagnosis is often a turning point toward answers and support. Because polyrrhinia is extremely rare, the diagnosis often involves a team that includes newborn, ear, nose, and throat, imaging, and genetics specialists.
Doctors look closely at the shape of the nose, nostrils, and midface, and check how well breathing and feeding are working. Visible clinical features are often the first step in the diagnosis of polyrrhinia.
Ultrasound may sometimes show an unusual nose shape before birth, especially later in pregnancy when facial features are easier to see. Fetal MRI can give a clearer view of the face and nearby tissues when doctors need more detail.
Imaging of the face and skull helps show how the nasal passages, sinuses, and surrounding bones developed. These imaging findings help plan care and check for differences that are not obvious from the outside.
Doctors may examine the nasal passages and breathing to see whether air can move through the nose normally. In some babies, a small camera exam is used to look closer at the inside of the nose and upper airway.
How is Polyrrhinia diagnosed?
Polyrrhinia is usually diagnosed at birth or even before birth on an ultrasound because the nose looks clearly different from usual. After that, doctors often use imaging scans such as CT or MRI, which are detailed pictures of the face and head, to see how the nasal passages and nearby bones and tissues are formed and to check for any other differences. Genetic testing may sometimes be offered to look for an underlying genetic cause, but the diagnosis itself is mainly based on the physical appearance and the imaging findings.
Stages of Polyrrhinia
Polyrrhinia does not have defined progression stages. This is because it is a very rare difference in facial development that is present before birth, rather than an illness that steadily worsens over time. Doctors usually start with a conversation about the baby’s appearance and breathing or feeding, then confirm the findings with a physical exam and imaging tests such as ultrasound before birth or scans after birth. In practice, how polyrrhinia is diagnosed and monitored depends on which nearby structures are also affected, so care often includes checks by ear, nose, and throat, craniofacial, and imaging specialists.
Outlook and prognosis
The outlook for polyrrhinia varies widely and depends mainly on whether it occurs alone or with other craniofacial, brain, or airway abnormalities. When the condition is isolated and reconstructive surgery is feasible, many children can survive and achieve good functional and cosmetic outcomes with staged multidisciplinary care. Prognosis is less favorable when polyrrhinia is accompanied by major associated anomalies, especially holoprosencephaly or other severe midline brain malformations, which can cause significant developmental impairment and increase the risk of early death. Because so few cases have been reported, precise survival statistics are not available, but mortality appears to be driven largely by the presence and severity of associated defects rather than the duplicated nasal structures themselves. Long-term quality of life often depends on airway function, feeding, hearing, speech, and the need for repeated craniofacial procedures over time.
Long-term effects
Polyrrhinia can affect day-to-day life in several ways over time, especially breathing, feeding, speech, and facial growth. Long-term effects vary widely, particularly when polyrrhinia happens along with differences in the palate, eyes, skull, or brain. Doctors may track these changes over years to see how breathing, hearing, development, and appearance evolve as a child grows.
Narrow or unusually shaped nasal passages can lead to ongoing blocked breathing, noisy breathing, or sleep-related breathing problems. Some of the early symptoms of polyrrhinia can continue into later childhood if the airway remains crowded or changes with growth.
In infancy, trouble coordinating breathing and feeding can make weight gain slower or feeding more tiring. For many living with polyrrhinia, this improves with growth, but some continue to have eating or growth challenges if other facial differences are also present.
If polyrrhinia occurs with changes in the palate or nasal passages, speech may sound unusually nasal or be harder to understand. As children get older, articulation and resonance problems can persist, especially when airflow through the nose is not typical.
Some people with polyrrhinia also have a higher chance of middle ear problems, which can affect hearing over time. Repeated ear fluid or hearing loss can then influence speech and language development.
How is it to live with Polyrrhinia?
Living with polyrrhinia can be very different from one person to another, because the condition is extremely rare and often comes with other facial or skull differences that shape daily needs. For some people, the main challenges are practical, such as breathing through the nose, feeding in infancy, repeated medical visits, and one or more reconstructive surgeries, while for others the social side can be just as important because visible facial differences often draw attention, questions, or staring. Families and other close supports may take on a large role in medical care, advocacy, and emotional support, but with skilled care and a supportive environment, many people can build routines that protect both health and confidence.
Treatment and drugs
Treatment for polyrrhinia depends on how the extra nasal structures affect breathing, feeding, smell, and facial development in daily life. Because polyrrhinia is present from birth and often comes with other differences in the face or skull, care is usually planned by a team that may include ear, nose, and throat specialists, craniofacial surgeons, and imaging experts. Treatment plans often combine several approaches: careful scans to map the anatomy, support for breathing or feeding if needed, and surgery to remove or reshape nasal tissues when this is likely to improve function or appearance. Surgery is usually tailored to the child’s exact anatomy rather than following one standard operation, and timing can vary depending on symptoms, growth, and overall health. Not every treatment works the same way for every person.
Can you cure Polyrrhinia?
No, there is no cure for polyrrhinia, because it is a condition a baby is born with that affects how the nose forms. Treatment usually focuses on surgery and supportive care to improve breathing, feeding, appearance, and any related problems, and some children may need more than one procedure over time.
Non-drug treatment
Living with polyrrhinia can affect breathing, feeding, appearance, and later speech, so care is usually planned around daily needs from the start. Polyrrhinia is very rare, and treatment is highly individualized based on how the nose and nearby facial structures formed. For many, treatment begins not at the pharmacy, but with a craniofacial team that plans supportive care and, when needed, surgery. The best treatment for polyrrhinia often combines practical support in infancy with longer-term reconstructive and developmental care.
Care is usually coordinated by a craniofacial team that may include surgeons, ear, nose, and throat specialists, feeding experts, and speech therapists. This helps families make decisions in a step-by-step way and match treatment to breathing, feeding, and facial development.
Surgery is often the main non-drug treatment when extra nasal structures affect breathing, appearance, or both. The goal is to create a safer airway and a more typical nose shape while protecting nearby tissues as the face grows.
Some babies with polyrrhinia need help keeping airflow steady, especially if the nasal passages are narrow or blocked. Support may include positioning, suction, close monitoring, or temporary breathing assistance before or after surgery.
Feeding support can be important when nasal differences make sucking, swallowing, or coordination harder. Structured programs, like feeding therapy and lactation support, can help babies get enough nutrition and lower the risk of choking or tiring out during feeds.
Your genes may have an impact on how drugs work for you
Polyrrhinia is a very rare condition present from birth, and there are no well-established genetic findings that are known to change how medicines work specifically for people living with it. For many, care is mainly based on symptoms and, in some cases, surgery, so medication choices are usually guided more by age, overall health, breathing or feeding needs, and any other medical conditions than by inherited differences in drug response. If a child or adult with polyrrhinia needs medicines for pain, infection, anesthesia, or another common issue, the medical team will usually choose and adjust them based on the person’s needs rather than on a known gene-based medicine effect for this condition.
Pharmacological treatments
For people living with polyrrhinia, medicines usually do not treat the underlying condition because it is a rare structural difference present from birth. Care is most often centered on surgery and airway support, while drugs are used for comfort, infection treatment, or short-term care around procedures. Sometimes medicines are taken short-term, while others are used long-term only if related nose symptoms are also present.
There is no medicine that can remove or correct polyrrhinia itself. Treatment is usually planned by a craniofacial or ear, nose, and throat team, with drugs used only to manage symptoms or support surgery.
Acetaminophen and ibuprofen may be used for discomfort, especially after procedures or if there is irritation around the nose. These medicines help with pain and swelling, but they do not change the structure causing the problem.
If there is a bacterial infection, doctors may prescribe antibiotics such as amoxicillin-clavulanate or cephalexin, depending on age and the likely germ. This may be more relevant if crusting, drainage, or other early symptoms of polyrrhinia are linked to blockage or infection.
Saline nasal spray is often used to loosen mucus and keep the nasal passages moist. In some cases, doctors may also use a short course of a nasal steroid such as fluticasone if swelling from allergies or inflammation is adding to breathing problems.
Genetic influences
When a baby is born with polyrrhinia, families often want to know why it happened and whether it could happen again. Many families ask whether polyrrhinia is genetic, but in most reported cases there is no clear inherited pattern and the change seems to happen very early in pregnancy as the center of the face is forming. Researchers think genes that guide early facial development may sometimes be involved, especially when polyrrhinia appears along with other birth differences, but no single gene explains most cases. Because this condition is so rare, doctors often look at the whole picture, including family history, the baby’s other findings, and sometimes chromosome or gene testing. To put these pieces together, doctors may suggest genetic counseling. This can help families understand whether the chance of polyrrhinia happening again is likely to be low or whether more testing could give clearer answers.
Is Polyrrhinia genetic?
Genetics may play a role in Polyrrhinia, but the exact cause is still unclear because so few cases have been reported. Many cases seem sporadic, though changes affecting early facial development could contribute in some people with Polyrrhinia.
Having a genetic risk is not necessarily a diagnosis
Genetic variants are a usual part of human biology and are common across the general population. Most of them do not have a direct effect on health and are simply part of the natural differences seen among people. With many genes, having a variant connected to a condition suggests a possible link rather than a certain diagnosis, especially when several genes and environmental factors are involved. In some cases, though, one well-understood variant in a particular gene can be enough to confirm a diagnosis.
Pharmacogenetics—how genetics influence drug effects
For families dealing with polyrrhinia, treatment usually focuses on safe breathing, feeding, and carefully planned surgery rather than long-term medicines. Because polyrrhinia is a structural difference present from birth, there is no drug that corrects it, and doctors usually tailor care to the exact anatomy and to any other health issues a child may have. Genetic testing may be offered to look for an underlying syndrome or chromosome change, especially if polyrrhinia appears along with other birth differences, and that information can help guide screening and the timing of treatment options for polyrrhinia. Genetics is only one factor, and at this point there are no well-established pharmacogenetic rules that tell doctors which medicine will work differently specifically because of polyrrhinia. In practice, genetic results are more often used to understand the bigger health picture and plan coordinated care than to choose a specific drug for polyrrhinia itself.
Interactions with other conditions
Polyrrhinia does not usually “interact” with common adult illnesses in the way diabetes or asthma might, but it can appear together with other rare birth differences that affect the face, airways, or brain. Doctors call it a “comorbidity” when two conditions occur together. In some babies with polyrrhinia, there may also be a cleft lip or palate, differences in the eyes or skull, or less often brain abnormalities, and these related conditions can have a bigger effect on breathing, feeding, hearing, and development than the extra nasal tissue itself. Day to day, this can mean that what seems like simple nasal blockage may actually be linked to a wider craniofacial problem, especially when early symptoms of polyrrhinia are noticed soon after birth. Because polyrrhinia is so rare, care is usually planned by a team that may include ear, nose, and throat specialists, craniofacial surgeons, and neurologists if other conditions are present.
How genes can cause diseases
Humans have more than 20,000 genes, each carrying out one or a few specific functions in the body. One gene instructs the body to digest lactose from milk, another tells the body how to build strong bones and another prevents the body's cells from beginning to multiply uncontrollably and developing into cancer. As all of these genes combined are the building instructions for our body, a defect in one of these genes can have severe health consequences.
Through decades of genetic research, we know the genetic code of any healthy/functional human gene. We have also identified that in certain positions on a gene, some individuals may have a different genetic letter from the one you have. We call these hotspots "Genetic Variations" or "Variants" in short. In many cases, studies have been able to show that having the genetic letter "G" in the position makes you healthy, but having the letter "A" in the same position disrupts the gene function and causes a disease. Genopedia allows you to view these variants in genes and summarizes all that we know from scientific research, which genetic letters (Genotype) have good or bad consequences on your health or on your traits.
What other conditions can cause similar symptoms to Polyrrhinia?
Because polyrrhinia is a very rare birth difference that changes the shape of the nose, doctors often also consider a split nose, an unusually wide nose caused by differences in how the middle of the face formed before birth, facial clefts, or a lump in the center of the nose such as a cyst. These conditions can look similar at first, so the care team usually checks for other changes in the face, skull, or brain to tell them apart.
History
For families, polyrrhinia usually enters the story at birth, when a baby is found to have two noses or a split, duplicated nose structure. Because it is so rare, most of what doctors know has come from individual case reports rather than large studies. In recent decades, awareness has grown as imaging, surgery, and careful long-term follow-up have made it easier to describe the condition in more detail.
Earlier medical reports focused mainly on what could be seen from the outside. As doctors learned more, they recognized that polyrrhinia can vary a lot from one child to another. Some babies have a more complete duplication, while others have a partial split of the nose, and some also have differences in nearby structures of the face, eyes, or brain. That helped move medical understanding beyond simple description toward a fuller picture of how the condition may affect breathing, feeding, and later reconstructive care.
The history of polyrrhinia is also the history of improving diagnosis. In older reports, doctors often relied on physical examination alone, but modern ultrasound, CT, and MRI scans have helped show how the nasal passages and surrounding tissues are formed before treatment is planned. This has been especially important because the early symptoms of polyrrhinia may include blocked airflow or trouble feeding in newborns, while in other cases breathing is less affected.
Over time, treatment has also changed. Earlier care was limited by the surgical tools and imaging available at the time, so operations were often based on what surgeons could assess during the procedure itself. Today, care is usually planned by a team that may include specialists in newborn medicine, ear, nose, and throat care, plastic and craniofacial surgery, and radiology. Researchers later identified that some cases are linked to changes that happen very early in development, but because polyrrhinia is so uncommon, many questions about why it happens and why it varies so much are still being studied.