What are the signs and symptoms of Opitz G/BBB syndrome? Opitz G/BBB syndrome mainly affects structures along the midline of the body. The most common features of the condition are wide-spaced eyes (hypertelorism); defects of the larynx, trachea, and/or esophagus causing breathing problems and difficulty swallowing (dysphagia); and in males, the urethra opening on the underside of the penis (hypospadias). Mild intellectual disability and developmental delay occur in about 50 percent of people with Opitz G/BBB syndrome. Delays in motor skills, speech delays, and learning difficulties may also occur. Some individuals with Opitz G/BBB syndrome have features similar to autistic spectrum disorders, including impaired communication and socialization skills. About half of affected individuals also have cleft lip with or without a cleft palate. Some have cleft palate alone. Heart defects, an obstruction of the anal opening (imperforate anus), and brain defects such as an absence of the tissue connecting the left and right halves of the brain (agenesis of the corpus callosum) occur in less than 50 percent of those affected. Facial abnormalities that may be seen in this disorder can include a flat nasal bridge, thin upper lip, and low set ears. These features vary among affected individuals, even within the same family. The signs and symptoms of the autosomal dominant form of the condition are comparable to those seen in the X-linked form. However, the X-linked form of Opitz G/BBB syndrome tends to include cleft lip with or without cleft palate, while cleft palate alone is more common in the autosomal dominant form. Females with X-linked Opitz G/BBB syndrome are usually mildly affected, as hypertelorism may be the only sign of the disorder. The Human Phenotype Ontology provides the following list of signs and symptoms for Opitz G/BBB syndrome. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms. Signs and Symptoms Approximate number of patients (when available) Abnormality of the pharynx 90% Anteverted nares 90% Displacement of the external urethral meatus 90% Epicanthus 90% Abnormality of the voice 50% Cognitive impairment 50% Respiratory insufficiency 50% Increased number of teeth 7.5% Low-set, posteriorly rotated ears 7.5% Pectus carinatum 7.5% Pectus excavatum 7.5% Prominent metopic ridge 7.5% Reduced number of teeth 7.5% Sensorineural hearing impairment 7.5% Craniosynostosis 5% Abnormality of cardiovascular system morphology - Abnormality of the kidney - Abnormality of the nasopharynx - Abnormality of the ureter - Absent gallbladder - Agenesis of corpus callosum - Anal atresia - Anal stenosis - Aplasia/Hypoplasia of the cerebellar vermis - Aspiration - Atria septal defect - Autosomal dominant inheritance - Bifid scrotum - Bifid uvula - Cavum septum pellucidum - Cerebellar vermis hypoplasia - Cerebral cortical atrophy - Cleft palate - Cleft upper lip - Coarctation of aorta - Conductive hearing impairment - Cranial asymmetry - Cryptorchidism - Depressed nasal bridge - Diastasis recti - Dysphagia - Frontal bossing - Gastroesophageal reflux - Hiatus hernia - High palate - Hypertelorism - Hypospadias - Inguinal hernia - Intellectual disability - Laryngeal cleft - Muscular hypotonia - Patent ductus arteriosus - Posterior pharyngeal cleft - Posteriorly rotated ears - Prominent forehead - Pulmonary hypertension - Pulmonary hypoplasia - Short lingual frenulum - Smooth philtrum - Strabismus - Telecanthus - Tracheoesophageal fistula - Umbilical hernia - Ventricular septal defect - Ventriculomegaly - Weak cry - Wide nasal bridge - Widow's peak - X-linked recessive inheritance - The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature. The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined. Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.