Progressive familial intrahepatic cholestasis type 2 (PFIC2) is a liver condition. Children who are affected by PFIC2 cannot drain bile from the liver. The buildup of bile causes liver disease that gets worse over time and often causes liver failure or cirrhosis in the first few years of life. There are a number of signs of syptoms that begin in infancy. These can include severe itching, yellowing of the skin and whites of the eyes (jaundice), inability to gain weight or grow at the expected rate, high blood pressure in the vein that supplies blood to the liver, and an enlarged liver and spleen. People with PFIC2 are also at increased risk of developing a type of liver cancer called hepatocellular carcinoma.
Changes in the same gene can also cause less severe form of PFIC2. People may experience episodes of cholestasis, but these typicall resolve and do not cause lasting damage to the liver. When these episodes occur during pregnancy (intrahepatic cholestasis of pregnancy), it can cause problems for the unborn baby and can increase the risk of premature delivery or stillbirth. Medicines can help relieve the itching. In severe cases, surgical treatment (liver transplantation or partial external biliary diversion) is usually necessary for survival.
As humans we have about 23,000 genes. These genes are like tiny instruction manuals that influence our health, growth and development. We inherit half of our genes from our biological mum and the other half from our biological dad. These genes are lined up on structures called chromosomes. Most of us have 23 pairs of chromosomes. The first 22 pairs are called autosomes and for the most part - these are the same among men and women. The 23rd pair determine our sex - two X chromosomes for a female and one X and one Y chromosome for males.
Progressive familial intrahepatic cholestasis type 2 is known as an autosomal recessive condition. For autosomal recessive conditions, if a person has a variation in one copy of their gene, they are a carrier. This means that they are healthy because they also have a working copy of the gene. But, they can still pass their non-working copy to their child.
If the other parent also happens to be a carrier of the same gene, there is a 25% (1 in 4) chance that they both pass this gene variation on to their child — and as such, have a child affected by the disease.
If both parents are carriers of Progressive familial intrahepatic cholestasis type 2, there’s a one in four chance that their children could develop symptoms.
Carrier testing is like a checkup for your genes. It tests to see if you carry a gene variation that could cause a serious genetic disease in your child. Eugene offers an inclusive genetic carrier screening panel that includes Progressive familial intrahepatic cholestasis type 2, but there's a total 301 conditions that can be tested.
Eugene’s carrier test is a clinical grade test that can be done from the comfort of your own home — it’s just a saliva test. You're also paired with a genetic counsellor who provides mindful support and guidance every step of the way.Learn more about carrier screening
The biggest benefit of screening for Progressive familial intrahepatic cholestasis type 2 is that it can help future parents understand their reproductive risk so they can be ready and empowered to make more informed decisions. If neither partner are carriers, it provides reassurance and peace of mind that the risk of having a child with a genetic disease is low.
Since 90% of children that have a recessive genetic disease like Progressive familial intrahepatic cholestasis type 2 had no previous family history of it, it often feels completely out of the blue for the parents. Getting screened is a way to know this risk in advance, which can help familes manage or even prevent the disease in the first place.