Opitz G/BBB syndrome

Opitz G/BBB syndrome, also known as Opitz syndrome, G syndrome or BBB syndrome, is a rare genetic disorder affecting physical structures along the midline of the body. The letters G and BBB stand for the surnames of the families in which it was first diagnosed, and the name Opitz honors the physician who first described its signs and symptoms. There are two forms, an X-linked recessive form (type I) and an autosomal dominant form (type II), which share common physical deformities although their inheritance differs. Older names no longer in use include hypospadias-dysphagia syndrome, Opitz-Frias syndrome, telecanthus with associated abnormalities and hypertelorism-hypospadias syndrome. The X-linked form is estimated to affect one in 50,000 to 100,000 males and is thought to be under-diagnosed, while the autosomal dominant cases are grouped under 22q11.2 deletion syndrome.