A disease of the first weeks of life, in which the bile ducts outside the liver progressively scar shut. A genome-wide study of 200 Chinese infants with the condition found one locus near a gene involved in inflammation — evidence for a genetic contribution to a disease usually described only by what triggers it, which remains unknown.
Biliary atresia is a disease of infancy in which the bile ducts outside the liver progressively scar and close off, usually becoming apparent in the first few weeks of life. Without treatment, bile cannot drain from the liver, and the disease advances to cirrhosis. Even with early diagnosis and surgery, many children go on to need a liver transplant.
The cause of biliary atresia is not established. The leading theory, as the study behind this page states it, is that some still-unidentified factor in the perinatal period — possibly a virus or another environmental trigger — meets the immune system of a genetically susceptible infant, and the resulting immune response is what scars the bile ducts shut rather than clearing whatever triggered it. That theory is why a genetic study of the disease is worth doing at all: not to find "the" cause, but to find who is susceptible to whatever the real trigger turns out to be.
The study behind this page genotyped nearly 500,000 positions across the genome in 200 Chinese infants with biliary atresia and 481 ethnically matched controls, then tested the ten strongest signals in a further 124 cases and 90 controls. The strongest and only genome-wide significant result was rs17095355 on chromosome 10q24, downstream of XPNPEP1 — a gene involved in metabolizing inflammatory signalling molecules, which fits the immune-response theory of the disease without proving it.
This is a single study, in one population, and the page says so rather than implying a broader base of evidence. Biliary atresia is known to occur at different rates in different populations — it is notably more common in East Asia than in Europe or North America — and whether this same locus matters outside Chinese cohorts has not, to this page's sources, been separately tested.
Biliary atresia is diagnosed in infancy through a combination of blood tests, imaging and, definitively, a liver biopsy or intraoperative exploration — not through genetic testing, and this locus is not a diagnostic marker. The standard treatment, the Kasai procedure, reconnects the liver directly to the small intestine and works best when done early; many children still progress to needing a liver transplant regardless of genotype.
This is not a screening test. No genetic test, including this variant, is used to diagnose or predict biliary atresia in clinical practice. A jaundiced infant, especially one whose jaundice persists past two weeks or whose stools are pale, needs prompt medical evaluation regardless of any genotype.
What a 23andMe/AncestryDNA export or raw VCF can and can't tell you about Biliary Atresia comes down to these specific, well-studied positions — not a diagnosis.
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Biliary Atresia. MyGeneLog™. https://www.mygenelog.com/conditions/biliary-atresia
No. This is a research finding about genetic susceptibility in one population, not a diagnostic or screening test. Biliary atresia is diagnosed through clinical evaluation, imaging and biopsy, and prompt evaluation of a jaundiced infant matters regardless of genotype.
It is not established. The leading theory is that an unidentified perinatal factor — possibly viral — triggers an immune response in a genetically susceptible infant, and that response is what scars the bile ducts shut. This page's finding is about the susceptibility side of that theory, not the trigger.
Unknown. The study behind this page was conducted entirely in Chinese cohorts, and biliary atresia itself is known to be more common in East Asian populations. Whether the same locus matters elsewhere has not been separately tested, to this page's sources.
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