The importance to track variants in genes causing recessive disorders within the family: a FH/sitosterolemia clinical case

Familial hypercholesterolemia (FH) is a common disorder of lipid metabolism. However there are other rare disorders presenting a similar phenotype as Sitosterolemia, where the patient also presents with high LDL values. Sitosterolemia is a rare autosomal recessive disorder, manifested by extremely elevated plant sterols (PS) in plasma and tissue, leading to xanthomas and premature atherosclerotic disease. This disease is caused by mutations in either of two adjacent genes that encode ABC transporters, ABCG5 and ABCG8, responsible for the majority of sterol secretions into bile. Both disorders can cause premature atherosclerosis but have distinctive dietetic and therapeutic intervention. In the Portuguese Familial Hypercholesterolemia Study we have 348 FH mutation negative patients that could have another genetic cause for their hypercholesterolemia. The aim of this study is the clinical molecular report of a case belonging to this group.