Homozygosity for a FBN1 missense mutation: clinical and molecular evidence for recessive Marfan syndrome.

Marfan syndrome (MFS) is known as an autosomal-dominant connective tissue disorder (MIM 154,700), involving primarily the skeletal, ocular and cardiovascular systems, and caused by mutations in the gene for fibrillin1 (FBN1). Here, we report on two cousins from a consanguineous family with a homozygous c.1,453C>T FBN1 mutation (p.Arg485Cys) and MFS. All four healthy parents were heterozygous for the c.1,453C>T FBN1 mutation and none fulfilled the Ghent criteria for MFS. This family is the first molecularly confirmed recessive MFS. The demonstration of recessive cases of MFS has obvious implications for genetic counselling as well as for molecular diagnosis.