New Research Offers Important Insights into Birt–Hogg–Dubé Syndrome

A major new scientific publication brings together the latest understanding of Birt–Hogg–Dubé syndrome (BHD), highlighting important advances in research, diagnosis and care, as well as promising directions for future treatments.

For people living with BHD and their families, understanding the condition and how research is progressing can make a real difference.

A new review, published in October 2026 in the prestigious scientific journal Nature Reviews Disease Primers, provides a comprehensive overview of what researchers currently know about BHD syndrome.

Led by Professor Stefan Marciniak, alongside an international team of leading BHD researchers and clinicians, the publication explores how common BHD may be, why it affects different parts of the body, how it can be diagnosed and managed, and where future research could lead.

At The BHD Foundation, we welcome this important contribution to BHD research and want to share some of its key findings with our community.

BHD May Be Much More Common Than Previously Thought

One of the most significant findings highlighted in the publication is that BHD may be considerably more common than previously believed.

Historically, BHD has been considered an extremely rare genetic condition, with estimates suggesting that approximately five people in every million were affected.

However, recent genetic studies have challenged this understanding.

By examining genetic information from large populations, researchers have found that changes in the FLCN gene associated with BHD may occur in approximately 1 in every 3,000 people.

This is around 66 times higher than previous estimates based on clinically diagnosed cases.

Importantly, this does not mean that everyone carrying an FLCN gene change will experience symptoms or develop complications. BHD can affect people very differently, and some individuals may have few or no noticeable symptoms.

Instead, the findings suggest that many people with BHD may be living without a diagnosis.

Why does this matter?

Earlier diagnosis can help people access appropriate monitoring, particularly for kidney tumours, and allows family members to understand whether they may also be affected.

The findings reinforce the importance of increasing awareness of BHD among healthcare professionals and the wider public.

Understanding Why BHD Affects the Kidneys, Lungs and Skin

BHD is caused by changes in a gene called FLCN, which provides instructions for producing a protein known as folliculin.

Folliculin plays an important role in regulating how cells grow, respond to nutrients and maintain their normal functions.

When this protein does not work as expected, it can affect different parts of the body.

The three main areas associated with BHD are:

• Kidneys: An increased risk of developing kidney tumours, some of which can become cancerous.

• Lungs: The development of air-filled cysts and an increased risk of a collapsed lung, known medically as a pneumothorax.

• Skin: Small, usually harmless bumps called fibrofolliculomas, which often appear on the face, neck or upper body.

Not everyone with BHD experiences all three manifestations, and the severity can vary considerably, even between members of the same family.

The new publication highlights advances in understanding how changes in folliculin affect the body's cellular signalling systems.

In particular, researchers are learning more about pathways involving proteins called mTORC1, TFEB and TFE3, which help regulate important activities within our cells.

Although these scientific processes are complex, understanding them is an important step towards identifying potential treatments.

Kidney Monitoring Remains Essential

One of the most important messages from the review is the continued need for regular kidney monitoring.

People with BHD have an increased risk of developing kidney tumours. Although many BHD-associated kidney tumours grow slowly, some can become cancerous.

Regular imaging allows healthcare professionals to identify changes early and decide whether treatment is needed.

The publication reinforces current recommendations that kidney surveillance should generally begin at around 20 years of age and continue throughout life.

MRI scans are preferred for monitoring because they can identify smaller abnormalities that may not always be visible on ultrasound.

The review discusses screening intervals of between one and three years, depending on the guidance followed and individual circumstances. People who already have kidney tumours may require more frequent monitoring.

For people living with BHD, the key message is that regular kidney monitoring remains one of the most effective ways to manage the condition and reduce the risk of serious complications.

If you have BHD and are unsure about your kidney monitoring arrangements, speak to your specialist team.

Reassuring Findings About Lung Health

Lung cysts are common in people with BHD and can increase the risk of a spontaneous pneumothorax, or collapsed lung.

However, the review also highlights some reassuring findings.

Although lung cysts may slowly increase in size over time, lung function generally remains well preserved in most people with BHD.

This means that having lung cysts does not necessarily mean that someone will experience progressive breathing difficulties.

The main concern remains the risk of pneumothorax.

The publication emphasises the importance of recognising symptoms, understanding individual risks and discussing appropriate management with respiratory specialists.

People with BHD should seek urgent medical attention if they experience sudden chest pain or unexpected breathlessness, as these may be signs of a collapsed lung.

Why Genetic Testing Matters for Families

BHD is an inherited genetic condition.

If someone has a disease-causing change in the FLCN gene, each of their children has a 50% chance of inheriting that change.

However, inheriting the gene change does not mean that everyone will experience the same symptoms or complications.

The review highlights the importance of genetic counselling and testing for families affected by BHD.

When a specific FLCN gene change has been identified in a family, other relatives can be offered testing to establish whether they have inherited it.

This can help ensure that those who need kidney monitoring receive it, while avoiding unnecessary tests for relatives who have not inherited the familial change.

Genetic counselling can also help families understand the condition and make informed decisions about their health.

Could This Research Lead to New Treatments?

One of the most encouraging areas discussed in the publication is the progress being made in understanding the biological processes behind BHD.

Researchers have identified important changes in how cells behave when folliculin is not functioning normally.

These discoveries are helping scientists explore potential ways to target the processes involved in kidney tumour development and other BHD-related complications.

However, it is important to recognise that these findings have not yet resulted in an established treatment that corrects the underlying genetic cause of BHD.

Much of the work remains at an early research stage, and further studies are needed to determine whether these discoveries can lead to safe and effective treatments for patients.

Nevertheless, understanding the mechanisms behind BHD is an essential foundation for developing future therapies.

Recognising the Emotional Impact of Living with BHD

The publication also acknowledges something that is particularly important to patients and families: the emotional and psychological impact of living with a lifelong genetic condition.

For some people, BHD involves regular hospital appointments, scans and uncertainty about whether kidney tumours or lung complications may develop.

Others may experience anxiety about passing the condition on to their children or worry about the health of family members.

Visible skin changes can also affect confidence and emotional wellbeing.

The review recognises that these experiences can have a significant impact on quality of life.

It highlights the importance of coordinated care, access to reliable information and support from healthcare professionals who understand the condition.

For The BHD Foundation, this reinforces why supporting people affected by BHD is just as important as improving scientific understanding.

What Does This Mean for the BHD Community?

This publication represents an important contribution to our understanding of BHD.

Although it does not announce a cure or a new treatment, it brings together growing evidence that could help shape the future of diagnosis, monitoring and research.

There are several particularly important messages for our community.

BHD may be more common than we thought. Greater awareness could help more people receive a diagnosis and access appropriate care.

Regular kidney monitoring remains vital. Early detection and appropriate management can make a significant difference.

Our understanding of BHD is improving. Researchers are gaining a clearer picture of how changes in the FLCN gene affect the body.

Future treatments remain an important research priority. Advances in understanding the biology of BHD are opening new possibilities for investigation.

The patient experience matters. Living with BHD involves more than managing physical symptoms, and emotional wellbeing must remain part of the conversation.

Looking Ahead

For many people affected by rare genetic conditions, scientific progress can sometimes feel slow.

However, publications such as this demonstrate how much our understanding of BHD has developed and how researchers around the world are continuing to build on that knowledge.

The growing evidence that BHD may be underdiagnosed also highlights the importance of raising awareness, improving access to genetic testing and ensuring that people receive appropriate specialist care.

At The BHD Foundation, we believe that research, awareness and patient support must go hand in hand.

We will continue to share developments in BHD research with our community, helping patients and families understand what new discoveries mean for them.

Every advance in understanding BHD brings us closer to better diagnosis, improved care and, we hope, more effective treatments in the future.

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About the Research

Publication: Birt–Hogg–Dubé syndrome

Authors: Stefan J. Marciniak, Andrea Ballabio, Elizabeth P. Henske, John C. Kennedy, W. Marston Linehan, Eamonn R. Maher, Neil Rajan, Maria T. Wetscherek and Kai-Feng Xu.

Journal: Nature Reviews Disease Primers

Published: 2026

DOI: 10.1038/s41572-026-00745-3

Read the original publication: https://doi.org/10.1038/s41572-026-00745-3

This blog provides a patient-friendly overview of the published scientific review. It is intended for information and awareness and should not replace individual medical advice. If you have questions about your diagnosis, monitoring or treatment, please speak to your healthcare team.