Opitz syndrome, also called Obitz G/BBB syndrome, is a genetic condition that causes midline abnormalities. Specifically, features of this condition include wide spaced eyes (hypertelorism) along with voice box (larynx) abnormalities, windpipe (trachea) abnormalities, or esophagus abnormalities, which can all cause difficulty with swallowing and breathing. It is also common to have a gap between the trachea and esophagus (laryngeal cleft) that can make it difficult to breathe while eating. Facial changes include a prominent forehead, widow’s peak hairline, flat nasal bridge, thin upper lip, and low set ears. About half of those affected have learning problems (intellectual disabilities) and delays in development. Other features may include a cleft in the lip and/or roof of the mouth (palate). Males sometimes have genital abnormalities, such as an opening on the underside of the penis (hypospadias) or undescended testes (cryptorchidism).
Opitz syndrome can be caused by changes (mutations) in two different genes, as well as a chromosome abnormality. However, each of these genetic causes lead to similar features. The most common cause of Opitz syndrome is a mutation in the MID1 gene located on the X-chromosome. Some cases of Opitz syndrome are caused by missing (deleted) genetic material (DNA) from the long arm of chromosome 22, at location 22q11.2. Other cases are caused by a mutation in the SPECC1L gene.
Opitz syndrome is usually diagnosed by a doctor who is familiar with genetic conditions (geneticist) and a diagnosis is confirmed with genetic testing. Treatment options depend on the complications a child may have and may require surgery. Therapies are helpful for children with developmental delays. If your child has been diagnosed with Opitz syndrome, talk with their doctor to discuss current treatment options. Support groups are available to connect with others affected by this condition.