The Human Phenotype Ontology (HPO) provides the following list of features that have been reported in people with this condition. Much of the information in the HPO comes from Orphanet, a European rare disease database. If available, the list includes a rough estimate of how common a feature is (its frequency). Frequencies are based on a specific study and may not be representative of all studies. You can use the MedlinePlus Medical Dictionary for definitions of the terms below.
| Signs and Symptoms | Approximate number of patients (when available) |
| Abnormality of the fontanelles or cranial sutures | 90% |
| Cognitive impairment | 90% |
| Cryptorchidism | 90% |
| Hypertelorism | 90% |
| Malar flattening | 90% |
| Male pseudohermaphroditism | 90% |
| Microcephaly | 90% |
| Neurological speech impairment | 90% |
| Abnormality of the heme biosynthetic pathway | 50% |
| Abnormality of the tongue | 50% |
| Anteverted nares | 50% |
| Autism | 50% |
| Depressed nasal ridge | 50% |
| Epicanthus | 50% |
| Everted lower lip vermilion | 50% |
| Hypoplasia of penis | 50% |
| Muscular hypotonia | 50% |
| Seizures | 50% |
| Short stature | 50% |
| Talipes | 50% |
| Telecanthus | 50% |
| Thick lower lip vermilion | 50% |
| Abnormality of movement | 7.5% |
| Abnormality of the kidney | 7.5% |
| Abnormality of the teeth | 7.5% |
| Aganglionic megacolon | 7.5% |
| Aplasia/Hypoplasia of the corpus callosum | 7.5% |
| Brachydactyly syndrome | 7.5% |
| Cerebral cortical atrophy | 7.5% |
| Clinodactyly of the 5th finger | 7.5% |
| Constipation | 7.5% |
| Encephalitis | 7.5% |
| Feeding difficulties in infancy | 7.5% |
| Flexion contracture | 7.5% |
| Hemiplegia/hemiparesis | 7.5% |
| Limitation of joint mobility | 7.5% |
| Myopia | 7.5% |
| Nausea and vomiting | 7.5% |
| Optic atrophy | 7.5% |
| Recurrent urinary tract infections | 7.5% |
| Self-injurious behavior | 7.5% |
| Sensorineural hearing impairment | 7.5% |
| Visual impairment | 7.5% |
| Volvulus | 7.5% |
| Abnormality of metabolism/homeostasis | - |
| Absent frontal sinuses | - |
| Cerebral atrophy | - |
| Clinodactyly | - |
| Coxa valga | - |
| Depressed nasal bridge | - |
| Gastroesophageal reflux | - |
| Hemivertebrae | - |
| Hydronephrosis | - |
| Hypochromic microcytic anemia | - |
| Hypospadias | - |
| Infantile muscular hypotonia | - |
| Intellectual disability | - |
| Kyphoscoliosis | - |
| Low-set ears | - |
| Macroglossia | - |
| Micropenis | - |
| Microtia | - |
| Perimembranous ventricular septal defect | - |
| Phenotypic variability | - |
| Posteriorly rotated ears | - |
| Postnatal growth retardation | - |
| Protruding tongue | - |
| Radial deviation of finger | - |
| Reduced alpha/beta synthesis ratio | - |
| Renal agenesis | - |
| Shawl scrotum | - |
| Short nose | - |
| Spasticity | - |
| Talipes equinovarus | - |
| Tapered finger | - |
| Umbilical hernia | - |
| U-Shaped upper lip vermilion | - |
| Widely-spaced maxillary central incisors | - |
| X-linked dominant inheritance | - |
Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.
The resources below provide information about treatment options for this condition. If you have questions about which treatment is right for you, talk to your healthcare professional.
Living with a genetic or rare disease can impact the daily lives of patients and families. These resources can help families navigate various aspects of living with a rare disease.
These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.
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My son was diagnosed with alpha-thalassemia x-linked intellectual disability syndrome. The questions I have relate to other members of the family. I have a sister who has children. I understand that if my sister has the mutation, there is a chance that she passed it to her daughter, who would then be a carrier. But the literature I have read isn't completely clear regarding boys. If my sister carries the mutation, could she have passed it to her son and could her son be an unaffected carrier of the mutation? See answer
