What is the prevalence of Dubin-Johnson syndrome?

Dubin-Johnson syndrome is a rare, benign, autosomal recessive disorder characterized by chronic conjugated hyperbilirubinemia. While exact global prevalence is unknown, it is considered a rare condition, though it is notably more common in specific populations, such as Iranian Jews, where the prevalence is estimated at approximately 1 in 1,300.

How common is Dubin-Johnson syndrome?

Because Dubin-Johnson syndrome is often asymptomatic or mild, it is frequently underdiagnosed, making precise prevalence data difficult to establish. In the general population, the disorder is considered rare. However, the frequency of Dubin-Johnson syndrome varies significantly by geography and ethnicity. The highest documented prevalence is found within the Iranian Jewish population, with estimates reaching 1 in 1,300 individuals. In most other global populations, the condition is significantly less common, though exact figures are not well-defined in epidemiological literature. Data from the DiseaseMaps.org community platform provides a vital real-world perspective, helping researchers connect with individuals living with this diagnosis to better understand the true impact and frequency of the condition beyond clinical trial settings.

Is there a difference in prevalence by gender or age?

Dubin-Johnson syndrome affects males and females with equal frequency, as the underlying genetic mutation occurs on an autosome rather than a sex chromosome. Regarding age of onset, the condition is typically identified in adolescence or early adulthood. While the genetic defect is present from birth, many individuals remain asymptomatic for years. Symptoms, most notably jaundice, are often triggered by secondary stressors such as infections, pregnancy, or the use of oral contraceptives. Because Dubin-Johnson syndrome is generally benign, many individuals may only be diagnosed incidentally during routine blood work or during a period of physiological stress.

Why is accurate data for Dubin-Johnson syndrome challenging to obtain?

The primary challenge in mapping the prevalence of Dubin-Johnson syndrome is its clinical presentation. Many people living with the condition experience no symptoms other than mild, intermittent jaundice, which may be misattributed to other liver conditions or simply overlooked. Clinical researchers face several hurdles when tracking cases:

• Asymptomatic nature: Many individuals never seek medical attention, meaning they are never included in clinical registries.


• Diagnostic overlap: It is frequently confused with Rotor syndrome, which also causes conjugated hyperbilirubinemia but lacks the characteristic liver pigmentation seen in Dubin-Johnson syndrome.


• Lack of universal screening: There is no standard neonatal or population-wide screening program, leading to a reliance on symptomatic presentation for diagnosis.

What is the genetic basis of the condition?

Dubin-Johnson syndrome is caused by mutations in the ABCC2 gene, which encodes the multidrug resistance-associated protein 2 (MRP2). This protein is responsible for transporting conjugated bilirubin from the liver cells into the bile ducts. When this protein is dysfunctional, bilirubin accumulates in the blood. Because it is an autosomal recessive disorder, an individual must inherit one mutated copy of the gene from each parent to manifest the clinical signs of the syndrome. Genetic counseling is highly recommended for families affected by Dubin-Johnson syndrome to understand the risks of transmission to future children.

Next steps

• Consult with a hepatologist or a gastroenterologist for an accurate diagnosis if you have unexplained persistent jaundice.


• Seek professional genetic counseling to discuss inheritance patterns and family testing if you have a confirmed diagnosis.


• Join the DiseaseMaps.org community to connect with other patients and contribute to a better understanding of this rare condition.


• Maintain a record of your liver function tests to share with healthcare providers during routine check-ups.

Medical disclaimer: This content is for informational purposes only and does not constitute medical advice, diagnosis, or treatment; always seek the advice of your physician or other qualified health provider with any questions regarding a medical condition.

References

• Orphanet: Dubin-Johnson syndrome (ORPHA:255).


• NIH Genetic and Rare Diseases Information Center (GARD): Dubin-Johnson syndrome.


• Online Mendelian Inheritance in Man (OMIM): #237500, Dubin-Johnson syndrome.


• PubMed/NCBI: Clinical and genetic studies on the ABCC2 gene and conjugated hyperbilirubinemia.