OPHN1 XLMR is a type of X chromosome linked genetic disorder that causes learning problems (intellectual disabilities), and is caused by a change (mutation) in the OPHN1 gene. Intellectual disability conditions that are caused by mutations in genes on the X chromosome are known as X-linked mental retardation (XLMR) conditions. OPHN1 XLMR causes intellectual disabilities that can range from mild to severe. Affected children, who are usually male, have low muscle tone (hypotonia), seizures, abnormal alignment of the eyes (strabismus), and poor coordination. The condition also causes unique facial features, including a long face, prominent forehead, deep-set eyes, and large ears. Underdeveloped genitals or undescended testes are also possible features. Females tend to be more mildly affected and can have mild learning disabilities, strabismus, and subtle facial features.
OPHN1 XLMR is the result of a change (mutation) in the OPHN1 gene, which is located on the X chromosome. This disorder is inherited in an X-linked manner. Males have one X chromosome (one copy of the OPHN1 gene) and females have two copies of the X chromosome (two copies of the OPHN1 gene). If a male has a mutation in his only copy of the gene, he will have OPHN1 XLMR. If a female has a mutation in one of her two copies, she still has one working copy of the gene and will likely have milder features.
Diagnosis of OPHN1 XLMR is usually considered in children who have the unique facial features and learning problems. The diagnosis is confirmed with genetic testing. Although there is no cure for the disease, therapies can help children with this condition reach their full intellectual potential. If your child has been diagnosed with OPHN1 XLMR, talk to your doctor about all current treatment options. Support groups are a good resource for additional information and connecting with other families affected by OPHN1 XLMR.