Bilirubin metabolism genetic diseases

Finally, there are hereditary causes of non-conjugated, nonhemolytic hyperbilirubinemias. These are Crigler-Najjar types 1 and 2 and Gilbert s syndrome (discussed in the section on Genetic Diseases of Bilirubin Metabolism). 

A number of genetic diseases are associated with defects in one or more of the enzymes involved in the metabolism of bilirubin. Three of these diseases result in elevated levels of unconjugated bilirubin, and two of these result in elevated levels of conjugated bilirubin. All three of the diseases that produce elevated levels of unconjugated bilirubin are related to defects in the level of expression or in the inherent activity of bilirubin-UDP-glucuronyltransferase (also called UGT1 Al).The mildest and most common of these disease is Gilbert syndrome, which is present in about 10% of the Caucasian population. 

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