Intellectual Developmental Disorder, X-Linked, Syndromic, Bain Type (MRXSB)

What is Intellectual Developmental Disorder, X-Linked, Syndromic, Bain Type (MRXSB)?

Intellectual Developmental Disorder, X-Linked, Syndromic, Bain Type is a rare genetic syndrome, the main symptoms of which include intellectual disability, autism, low muscle tone, and seizures. The syndrome only affects females, due to the way in which it is inherited.

This syndrome is also known as:
Mental Retardation, X-Linked Syndromic, Bain Type, but the term Mental Retardation is outdated.

What gene changes cause Intellectual Developmental Disorder, X-Linked, Syndromic, Bain Type (MRXSB)?

Mutations in the HNRNPH2 gene are responsible for causing the syndrome. The syndrome is an X-linked disorder.

Syndromes inherited in an X-linked recessive pattern generally only affect males. Males only have one X chromosome, and so one copy of a gene mutation on it causes the syndrome. Females, with two X chromosomes, only one of which will be mutated, are not likely to be affected.

Syndromes following an X-linked dominant inheritance pattern are caused by a mutation in a single copy of the gene. This mutation may occur in one of the two X chromosomes in females or the single X chromosome in males. Males typically experience more severe symptoms than females.

What are the main symptoms of Intellectual Developmental Disorder, X-Linked, Syndromic, Bain Type (MRXSB)?

The main symptoms of the syndrome include developmental delay as well as developmental regression. This means the loss of skills an individual has already acquired. Individuals generally do not develop speech. Some affected individuals also develop other disorders related to mental development including attention deficit hyperactivity disorder, anxiety, and obsessive-compulsive disorder. Autism is also diagnosed in some affected individuals.

Other symptoms include a small head, unique facial features (including a small jaw and wide-set eyes), and a short stature.

How is it diagnosed?

To find out if someone has a diagnosis of Intellectual Developmental Disorder, X-Linked, Syndromic, Bain Type (MRXSB), it is important to have a consultation and evaluation with a clinical genetic specialist.  Specialists may also suggest specific genetic testing or other types of tests to help reach a diagnosis.  FDNA’s AI technology can help speed up the diagnostic process by analyzing facial features and other health information.

More syndromes

Syndromes & Disorders

Ankyloblepharon-Ectodermal Defects-Cleft Lip/Palate Syndrome: Symptoms, Causes, Diagnosis, and Management 

Ankyloblepharon-ectodermal defects-cleft lip/palate syndrome, often shortened to AEC syndrome and also known as Hay-Wells syndrome, is a rare genetic condition that combines fused eyelids at birth with widespread skin, hair, and dental changes. AEC syndrome is an extremely rare ectodermal dysplasia that has been reported in a limited number of individuals worldwide. Because severe skin erosions in infancy […]

Read more
Syndromes & Disorders

Cranioectodermal Dysplasia: Symptoms, Causes, Diagnosis, and Treatment 

Cranioectodermal dysplasia, also known as Sensenbrenner syndrome, is a rare genetic ciliopathy that can affect the skull, skeleton, hair, teeth, nails, skin, kidneys, liver, eyes, and other organs. The combination and severity of features vary between individuals. Doctors first described it in 1975, and fewer than 100 affected individuals have been documented in the medical literature, […]

Read more