Alström syndrome

Alström syndrome, also called Alstrom-Halgren Syndrome, is a rare genetic disorder caused by mutations in the gene ALMS1. It is among the rarest genetic disorders in the world, as currently it has only 266 reported cases in medical literature and over 501 known cases in 47 countries. It was first described by Carl-Henry Alström in Sweden in 1959. Alstrom syndrome is sometimes confused with Bardet-Biedl syndrome, which has similar symptoms. Bardet-Biedl syndrome tends to have later onset in its symptoms. The risk where two carrier parents can both pass the gene and therefore have a child affected by the syndrome is 25% with each pregnancy. The risk to have a child who is the carrier of the gene like the parents is 50% with each pregnancy. A chance for a child to receive normal genes from both parents and be considered to be "genetically" normal is 25%. The risk for carrying the gene is equivalent for both male and female.