Maturity-onset diabetes of the young type 6 is a genetic form of diabetes that often starts in adolescence or early adulthood. People with Maturity-onset diabetes of the young type 6 usually have mild to moderate high blood sugar and few early symptoms, like increased thirst or frequent urination. It tends to run in families across generations and often stays relatively stable, but patterns can vary. Treatment often includes diet, exercise, and oral medicines, and some may need insulin over time. The outlook is generally good with regular care, and life expectancy is usually normal.
Overview
Maturity-onset diabetes of the young type 6Symptoms
Maturity-onset diabetes of the young type 6 often causes diabetes symptoms: increased thirst, frequent urination, fatigue, and blurry vision. Some people notice weight loss or infections that heal slowly. Early symptoms of MODY 6 can be mild or absent.
Outlook and prognosis
Most people with Maturity-onset diabetes of the young type 6 (MODY 6) lead full lives with careful glucose monitoring and tailored treatment. Blood sugar can be more variable, so regular follow-up helps prevent eye, kidney, and nerve problems. Family members may benefit from genetic counseling and testing.
Causes and risk factors
Maturity‑onset diabetes of the young type 6 results from a single gene change, usually in NEUROD1, inherited from one affected parent. Risk is higher with family history; weight gain, inactivity, pregnancy, and aging can unmask or worsen high blood sugar.
Genetic influences
Genetics are central in Maturity-onset diabetes of the young type 6, which stems from a single gene change and runs in families. One altered copy is usually enough to cause it. Specific variants can shape age at diagnosis, treatment response, and risks for relatives.
Diagnosis
Doctors suspect Maturity-onset diabetes of the young type 6 when diabetes starts young, autoantibodies are negative, and there’s a strong family pattern. Genetic testing confirms it. Ask about the genetic diagnosis of Maturity-onset diabetes of the young type 6.
Treatment and drugs
Maturity-onset diabetes of the young type 6 (MODY 6) is managed with tailored blood sugar control, often starting with healthy eating, activity, and glucose monitoring. Many need medication; responses vary from oral drugs to insulin. Genetic results guide choices and follow-up.
Symptoms
People with Maturity-onset diabetes of the young type 6 (MODY 6) often notice signs linked to higher blood sugar in the teen years or early adulthood. Early features of Maturity-onset diabetes of the young type 6 can include increased thirst, more frequent trips to the bathroom, and higher-than-expected blood sugar readings, even in people who aren’t overweight. Features vary from person to person and can change over time.
High sugar pulls water into the urine, so you may pee more often and feel very thirsty. Many people wake at night to urinate or carry water during the day.
When cells can’t use sugar well, energy drops. This can feel like midday fatigue, heavy legs on a short walk, or needing extra time to finish routine tasks.
Fluctuating sugar levels change the fluid balance in the eye, making vision blurrier. Reading screens or road signs may take more effort until levels settle.
If blood sugar stays high, the body loses calories in urine and breaks down fat and muscle. Clothes may feel looser even without dieting.
How people usually first notice Maturity-onset diabetes of the young type 6?
People often first notice maturity-onset diabetes of the young type 6 (MODY 6) when routine blood work shows high blood sugar in the teens or 20s, especially in families where several relatives developed “early diabetes” but were not overweight. Some have mild thirst, more frequent urination, or unexpected fatigue, while others feel fine and are flagged only by an elevated fasting glucose or A1C during a checkup. Because MODY runs in families in an autosomal dominant pattern, the first signs of MODY 6 are often recognized when a young person is tested after a parent or sibling is diagnosed.
Types of Maturity-onset diabetes of the young type 6
Maturity-onset diabetes of the young type 6 (often shortened to MODY 6) is a genetic form of diabetes caused by changes in the NEUROD1 gene. It tends to appear in teens or young adults, but age can vary within families. People may notice different sets of symptoms depending on their situation. When talking about types of MODY, each numbered MODY represents a different gene change, and symptoms can differ by variant and even within the same family.
MODY 6 basics
Caused by changes in the NEUROD1 gene, MODY 6 often leads to mild to moderate high blood sugar. Many are diagnosed in adolescence or young adulthood, sometimes after a routine blood test. Not everyone needs insulin right away.
Severity varies
Some people have only mild fasting glucose elevations for years, while others develop symptoms like thirst, frequent urination, or tiredness. Even within families, intensity can range from mild to severe. The balance of symptoms can shift over time.
Response to treatment
Many respond well to tablets that boost insulin release, while others may eventually need insulin. Treatment choice depends on blood sugar levels and life stage, including pregnancy. Keeping track of early symptoms of MODY 6 can help guide care.
Weight and features
People with MODY 6 are often not living with obesity, and diabetes can run across several generations. Doctors may find otherwise normal cholesterol and blood pressure. Some have no symptoms until a glucose test picks it up.
Comparison with other MODYs
Among types of MODY, MODY 6 generally has a milder course than some variants but can still progress. It may overlap with features of MODY 2 or MODY 3, so genetic testing is key. Having one type doesn’t necessarily mean you’ll develop the others.
What genetics can tell you about symptoms
In MODY 6, changes in the NEUROD1 gene can disrupt how pancreatic beta cells form and work, leading to mild to moderate high blood sugar. People may notice early-onset diabetes, frequent urination, thirst, and sometimes nighttime low blood sugar if on treatment.
Causes and risk factors
Maturity-onset diabetes of the young type 6 is usually caused by a change in the NEUROD1 gene that affects insulin-making cells. It often runs in families in an autosomal dominant pattern, so a child has a 50% chance of inheriting it if a parent carries the change. Genes set the stage, but environment and lifestyle often decide how the story unfolds. Weight gain, inactivity, or pregnancy can push blood sugar higher sooner and bring on early symptoms of Maturity-onset diabetes of the young type 6. Risk and age at diagnosis vary, and some people have no family history due to a new change in the gene.
Environmental and biological risk factors
Environmental and biological factors that raise the chance of Maturity-onset diabetes of the young type 6 are mainly those that increase new DNA changes around conception. Researchers are still exploring how outside influences interact with our inner biology. Most of these influences, when present, only shift risk slightly. Knowing the early symptoms of Maturity-onset diabetes of the young type 6 can support timely testing, but the items below focus on what can raise the chance of it occurring in the first place.
Children of older fathers tend to carry more new DNA changes that arise in sperm. This slightly increases the chance that a change affects pathways involved in insulin production and pancreatic development. The absolute risk for Maturity-onset diabetes of the young type 6 remains low in any one pregnancy.
Egg cells from older mothers are more prone to errors at conception. This can modestly raise the likelihood of a new change in a single gene in the child. Most pregnancies at advanced ages still do not involve such changes.
High-dose ionizing radiation to the pelvis or reproductive organs can damage DNA in sperm or eggs. Exposure shortly before conception may raise the chance of a new change present from birth, a rare step that could underlie conditions like Maturity-onset diabetes of the young type 6. Typical background levels and standard medical imaging are far below doses linked to this risk.
Certain chemotherapies and pelvic radiation can injure reproductive cells and DNA. Conceiving too soon after treatment may slightly increase the chance of new changes in a child. Following oncology guidance on timing helps lower this risk.
Genetic risk factors
In Maturity-onset diabetes of the young type 6 (MODY 6), inherited changes in a single gene called NEUROD1 lower the pancreas’s ability to release insulin. The condition usually follows an autosomal dominant pattern in families, meaning a parent can pass the gene change to a child. Carrying a genetic change doesn’t guarantee the condition will appear. Recognizing early symptoms of Maturity-onset diabetes of the young type 6 can prompt timely genetic testing and monitoring in families at risk.
NEUROD1 changes: Pathogenic changes in the NEUROD1 gene impair beta-cell function and insulin production. This single-gene cause defines MODY 6.
Autosomal dominant pattern: If a parent carries the NEUROD1 change, each child has a 50% (one-in-two) chance to inherit it. This inheritance pattern is typical for MODY 6.
Incomplete penetrance: Not everyone who inherits the NEUROD1 variant develops diabetes. Some have only mild, later-onset high glucose or remain unaffected.
Family history clues: Diabetes across several generations, often starting in adolescence or early adulthood, raises suspicion of a NEUROD1 variant. A clear vertical pattern in a family tree points toward MODY 6.
De novo occurrence: A NEUROD1 change can appear for the first time in someone with no family history. This is uncommon, but their children can still face a 50% (one-in-two) chance.
Variant type matters: Different NEUROD1 changes can influence how early blood sugar rises and how much insulin the body can make. Some mainly blunt insulin release after meals.
Other genetic modifiers: Additional genes may soften or intensify the effect of the NEUROD1 change. This helps explain why even close relatives can have different severities.
Lifestyle risk factors
Maturity-onset diabetes of the young type 6 is a genetic form of diabetes; lifestyle habits do not cause it, but they can strongly influence glucose levels, symptom swings, and the risk of complications. Understanding how lifestyle affects Maturity-onset diabetes of the young type 6 helps target daily choices that ease the demand on limited insulin secretion. The factors below focus on real-world habits that push glucose higher or lower and affect treatment safety, especially if you use insulin or sulfonylureas.
Refined carbs and sugary drinks trigger sharp post-meal spikes that the reduced insulin reserve in MODY 6 struggles to cover. Frequent spikes drive higher A1c and greater glucose variability.
Too little soluble fiber removes a natural brake on post-meal glucose rise in MODY 6. Adequate fiber lowers insulin demand and blunts peaks.
Skipping meals or large, infrequent eating causes wide glucose swings in MODY 6. If you use insulin or sulfonylureas, this pattern raises hypoglycemia risk between meals.
Limited movement reduces insulin sensitivity, forcing beta cells to work harder in MODY 6. This mismatch raises fasting and post-meal glucose.
Risk prevention
You can’t change the gene that causes Maturity-onset diabetes of the young type 6 (MODY6), but you can lower the chance of high sugars and long-term complications. Prevention is about lowering risk, not eliminating it completely. The goal is steady, safe glucose over years, using a mix of everyday habits and timely medical care. Family testing, smart monitoring, and early action—especially if you notice early symptoms of Maturity-onset diabetes of the young type 6 like increased thirst or frequent urination—make a real difference.
If one person is diagnosed with MODY6, close relatives may benefit from genetic counseling and testing. Finding it early lets families start monitoring and prevention sooner.
Track fasting glucose and A1C as advised, and consider home checks or a continuous monitor if recommended. Tightening up sooner helps prevent nerve, eye, kidney, and heart complications linked with MODY6.
Focus on vegetables, lean proteins, whole grains, and fiber to blunt glucose spikes. Spreading carbs across meals and snacks can steady sugars in MODY6.
Aim for regular activity most days to improve insulin sensitivity. Even brisk walks after meals can smooth post-meal glucose in MODY6.
Transmission
Maturity-onset diabetes of the young type 6 (MODY 6) is not contagious and cannot be caught from others. It’s usually passed down in families because of a change in a single gene; if a parent has this change, each child has about a 50% chance of inheriting it. This is the typical genetic transmission of maturity-onset diabetes of the young type 6, though a new gene change can occasionally appear in someone with no family history. Even within the same family, people who inherit the change may develop MODY 6 at different ages and with different levels of severity.
When to test your genes
Consider genetic testing if diabetes appears before age 25, runs across generations, or seems atypical for type 1 or type 2 (for example, stable mild fasting hyperglycemia, low insulin needs, or negative autoantibodies). Testing helps confirm MODY 6, guide medication choice, and inform screening for relatives.
Diagnosis
For many, the first step comes when everyday activities start feeling harder, like needing more water than usual or frequent bathroom trips. Doctors usually begin with your story and routine labs, then look for patterns that don’t fit type 1 or type 2 diabetes. With Maturity-onset diabetes of the young type 6, clues often include early-onset diabetes in a non‑obese person and a strong family pattern. A genetic test typically confirms what the clinical picture suggests.
Diabetes often starts in adolescence or early adulthood without significant overweight. Blood sugar may be mildly to moderately high at first, and some people do not need insulin right away. Over time, needs can change and treatment is adjusted.
A pattern of early-onset diabetes across generations raises suspicion for Maturity-onset diabetes of the young type 6. This autosomal-dominant pattern means first-degree relatives have a higher chance of being affected.
Fasting glucose and/or an oral glucose tolerance test show persistent high sugar levels (for example, fasting ≥126 mg/dL or ≥7.0 mmol/L). These tests help confirm diabetes and gauge severity.
HbA1c reflects average blood sugar over 2–3 months and may be mildly to moderately elevated (for example, ≥6.5% or ≥48 mmol/mol). Stable or slowly rising levels can point away from rapidly evolving type 1 diabetes.
Stages of Maturity-onset diabetes of the young type 6
Maturity-onset diabetes of the young type 6 does not have defined progression stages. Its course varies—a person’s blood sugar may stay only mildly high for years and then gradually rise—and care is guided by test results and treatment response rather than fixed stage labels. Doctors assess early symptoms of maturity-onset diabetes of the young type 6 such as increased thirst and frequent urination, look at family history, and use blood tests (fasting glucose and A1C), along with C‑peptide and antibody testing, to confirm the type and monitor control over time. Genetic testing may be offered to clarify certain risks.
Outlook and prognosis
Looking at the long-term picture can be helpful. For most people with Maturity-onset diabetes of the young type 6 (MODY 6), blood sugar tends to rise slowly over years, often first noticed as borderline readings in the teens or 20s. You might see early symptoms of MODY 6 such as thirst, more frequent urination, or fatigue during busy days, then feel fairly normal between episodes. Over time, most people can keep glucose in range with meal planning, activity, and medicine, though needs may change with age.
Prognosis refers to how a condition tends to change or stabilize over time. With consistent care, many living with MODY 6 avoid or delay eye, kidney, and nerve complications linked to long-term high sugar. Heart risk depends on overall factors like cholesterol, blood pressure, smoking, and family history, not just the diabetes type. Severe emergencies such as ketoacidosis are uncommon in MODY 6 but can occur if insulin needs are missed during illness or major stress.
Everyone’s journey looks a little different. Many people maintain good health for decades, and overall life expectancy is near typical when glucose, blood pressure, and cholesterol are well managed. There isn’t strong evidence that MODY 6 on its own shortens life, but poorly controlled sugar over many years can raise the risk of complications. Talk with your doctor about what your personal outlook might look like, including how genetics, lifestyle, and treatment choices shape the road ahead.
Long-term effects
Maturity-onset diabetes of the young type 6 is a genetic form of diabetes that often appears in adolescence or early adulthood, and its long-term picture is mostly shaped by how blood sugar trends over many years. Long-term effects vary widely, and not everyone experiences the same changes to the eyes, kidneys, nerves, or heart. Many recall that early symptoms of Maturity-onset diabetes of the young type 6 are subtle or absent, so changes can build slowly and show up later in life.
Blood sugar levels may remain mildly elevated for years or gradually become higher over time. The pace often reflects how much the insulin-making cells in the pancreas are affected.
Long-standing high sugar can damage the retina, leading to diabetic retinopathy. This may cause blurred vision or, in advanced cases, vision loss.
Tiny kidney filters can start leaking protein (microalbuminuria) after years of elevated sugar. This can progress to chronic kidney disease if the exposure continues.
Nerves in the feet and hands can become less sensitive after years of high glucose. Some develop tingling, burning pain, or numbness that affects balance and comfort.
How is it to live with Maturity-onset diabetes of the young type 6?
Living with maturity-onset diabetes of the young type 6 (MODY 6) often means managing blood sugar from a young age with routines that become second nature: regular checks, thoughtful meals, and planning for exercise, school, work, and travel. Because glucose levels can drift without dramatic symptoms, many build habits like carrying quick carbs, wearing medical ID, and sharing action plans with family, friends, teachers, or coworkers. For some, the diagnosis brings relief in understanding a family pattern; for others, it can feel like an invisible burden that requires steady attention but is very manageable with education and support. People around you may take on small roles—reminders, backup snacks, learning how to help in a low—turning everyday care into a team effort that keeps life moving smoothly.
Treatment and drugs
Treatment for maturity-onset diabetes of the young type 6 (MODY 6) focuses on keeping blood sugar in a steady, safe range while fitting care to each person’s pattern. Many people with MODY 6 start with healthy eating, regular physical activity, and glucose monitoring; doctors then add medicines based on how much insulin the body still makes and how high sugars run after meals. Treatment plans often combine several approaches, such as metformin to improve insulin sensitivity, a DPP-4 inhibitor or GLP-1 medicine to help the pancreas release insulin after meals, or insulin if sugars remain high or during times like illness, pregnancy, or surgery. Not every treatment works the same way for every person, so your doctor may adjust your dose to balance benefits and side effects and to meet targets like an A1C agreed upon together. Ask your doctor about the best starting point for you, and let your care team know about low or high readings, planned pregnancies, or new symptoms so they can fine-tune your plan.
Non-drug treatment
Non-drug care for Maturity-onset diabetes of the young type 6 focuses on steady blood sugar, protecting organs, and supporting family planning. Alongside medicines, non-drug therapies can help you keep glucose in range, reduce complications, and feel well day to day. Many strategies mirror type 1 and type 2 diabetes care but are tailored to your genetics and life stage. A diabetes educator or genetic counselor can help personalize a plan.
A balanced, lower-glycemic eating pattern helps smooth post-meal spikes. Regular meal timing and portion awareness support steady energy. A registered dietitian can tailor plans for school, work, and family life.
Moderate activity most days improves insulin sensitivity and glucose control. Aim for a mix of aerobic movement and simple muscle-strengthening. Start gradually and adjust around meals to prevent lows.
Checking levels with a meter or CGM guides daily decisions. Pattern spotting helps fine-tune meals, activity, and timing. Keep a log to share with your care team.
Skills-based training covers monitoring, meal planning, and sick-day steps. You’ll learn to notice early symptoms of Maturity-onset diabetes of the young type 6, like increased thirst or more frequent urination. Education is updated over time as needs change.
Your genes may have an impact on how drugs work for you
Genes can affect how people with maturity-onset diabetes of the young type 6 (MODY 6) respond to diabetes drugs—some may process medications faster or slower, changing effectiveness and side effects. Knowing the specific NEUROD1 variant can guide choices and dosing for safer, steadier glucose control.
Pharmacological treatments
Medicines for Maturity-onset diabetes of the young type 6 (MODY 6) are chosen based on your glucose patterns, age, and health goals, rather than a one‑size‑fits‑all plan. Treatment may shift over time, especially if glucose levels change, during pregnancy, or if lifestyle measures no longer cover your needs. Choices also reflect early symptoms of Maturity-onset diabetes of the young type 6 and how much the pancreas is still making insulin. Not everyone responds to the same medication in the same way.
Drugs like gliclazide, glipizide, or glimepiride help the pancreas release more insulin. They can work well in some people with MODY 6, especially when the body still makes insulin. Low blood sugar and weight gain are the main risks, so doses usually start low and are adjusted carefully.
This medicine lowers how much sugar the liver releases and helps the body use insulin better. It can be useful if there’s some insulin resistance or weight concerns. Stomach upset is the most common side effect and often improves after a few weeks.
Sitagliptin, linagliptin, saxagliptin, or alogliptin help your own insulin work longer after meals. They lower glucose modestly with a low risk of low blood sugar. Dose changes may be needed if you have kidney problems.
Liraglutide, semaglutide, or dulaglutide boost meal‑time insulin, curb appetite, and can aid weight loss. They are usually injections and may be added if oral medicines aren’t enough. Nausea is common early on and often eases with time.
Genetic influences
Maturity-onset diabetes of the young type 6 is usually driven by a single gene change that affects how the pancreas makes insulin. In many families, this follows what doctors call autosomal dominant inheritance—if a parent carries the gene change, each child has about a 50% chance of inheriting it. The gene most often involved is called NEUROD1; it works a bit like a dimmer switch for insulin‑producing cells, so when it’s turned down, keeping blood sugar steady can be harder. Even within the same family, some people develop diabetes in their teens or 20s while others with the same change have milder, later, or no symptoms at all. Family history is one of the strongest clues to a genetic influence. Genetic testing for Maturity-onset diabetes of the young type 6 can confirm the gene change and can guide care for you and relatives who may also be at risk.
Is Maturity-onset diabetes of the young type 6 genetic?
Genetics are central in Maturity-onset diabetes of the young type 6, which stems from a single gene change and runs in families. One altered copy is usually enough to cause it. Specific variants can shape age at diagnosis, treatment response, and risks for relatives.
Pharmacogenetics—how genetics influence drug effects
Knowing that your diabetes is maturity-onset diabetes of the young type 6 (MODY6) can shape which medicines are likely to help and how they’re dosed. Because MODY6 mainly affects the pancreas’s ability to release insulin, doctors may consider medicines that stimulate insulin release (such as sulfonylureas), often starting low and watching for low blood sugar, while recognizing that some people will still need insulin over time. Responses vary: one person may do well on tablets for years, while a sibling with the same diagnosis needs insulin earlier, so treatment is adjusted to your glucose patterns and goals. A “slow metabolizer” may process medicine more slowly and be more prone to side effects at standard doses. Pharmacogenetic testing, when available, can guide both the drug choice and the starting dose, alongside factors like weight, kidney function, and day-to-day glucose readings. If you’re comparing best treatment options for maturity-onset diabetes of the young type 6, a clinic experienced in MODY can help tailor therapy for you and advise relatives who may share similar medication responses.
Interactions with other conditions
Because MODY 6 affects how the pancreas makes insulin, other conditions that increase insulin resistance can make blood sugars harder to manage. A condition may “exacerbate” (make worse) symptoms of another, so weight gain, polycystic ovary syndrome, or taking steroids can push glucose higher than usual. MODY 6 can also be mistaken for type 1 or type 2 diabetes, especially if someone has an autoimmune illness or features of metabolic syndrome; this overlap can change which treatments work best. Heart and kidney health still matter over time, so high blood pressure or high cholesterol often travel alongside diabetes and raise cardiovascular risk; treating them reduces complications. During pregnancy, preexisting MODY 6 may interact with normal hormonal changes, sometimes requiring closer monitoring and medication adjustments for both parent and baby. If you notice early symptoms of Maturity-onset diabetes of the young type 6 while managing another chronic condition, let your care team know so your plan can be coordinated.
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.
History
Families and communities once noticed patterns: slim teenagers or young adults developing high blood sugar long before typical type 2 diabetes age, often across several generations. A grandparent, a parent, and then a teen might all need tablets rather than insulin at first, while others in the same family stayed unaffected. Doctors saw that this didn’t quite fit the usual types of diabetes.
First described in the medical literature as “maturity-onset diabetes of the young,” or MODY, the label grouped several look‑alike forms caused by different genes. Over time, descriptions became more precise as clinicians realized there wasn’t one single MODY, but many subtypes. Maturity-onset diabetes of the young type 6 (MODY 6) was named once researchers linked one of these patterns to a gene called NEUROD1, which helps the pancreas develop and regulates how insulin-producing cells work.
From early reports in the 1990s and early 2000s, families with MODY 6 often showed diabetes appearing in adolescence or early adulthood, sometimes with milder early symptoms of MODY 6 like increased thirst or frequent urination. Some had a parent with similar timing and treatment responses. Because blood tests for autoimmunity were negative and body weight was often average, doctors suspected a monogenic, or single‑gene, form. Genetic testing then confirmed the NEUROD1 link.
With each decade, scientists have clarified that MODY 6 is relatively rare compared with other MODY types such as MODY 2 and MODY 3. Still, the story of MODY 6 reflects a broader shift in diabetes care: moving from labels based on age and appearance to diagnoses grounded in gene changes and function. This matters in day‑to‑day care, because knowing the exact MODY type can guide medication choices, expected blood sugar patterns, and family screening.
Advances in genetics made testing more accessible, so more families with subtle or atypical features could be identified. As a result, the boundaries of MODY 6 became clearer—who tends to develop it, how early it shows up, and which treatments often help. Not every early description was complete, yet together they built the foundation of today’s knowledge.
Today, the history of MODY 6 is still being written. Registries, family studies, and long‑term follow‑up continue to refine our understanding. Looking back helps explain why some people were once misclassified as type 1 or type 2 diabetes, and why confirming MODY 6 can change both treatment and the conversation with relatives who may also want testing.