Alagille syndrome (arteriohepatic dysplasia) and del(20)(p11.2)

We report on a boy with Alagille syndrome. Chromosome analysis on a peripheral blood lymphocyte culture showed a de novo deletion of the short arm of chromosome 20 with a 46,XY,del(20)(p11.2) chromosome constitution. This is the second report of a del(20p) in a patient with Alagille syndrome. The possible localisation of this autosomal dominant syndrome on 20p is discussed.