U.S. flag

An official website of the United States government

Format

Send to:

Choose Destination

Intellectual developmental disorder, X-linked 108(MRX108)

MedGen UID:
1680544
Concept ID:
C5193009
Disease or Syndrome
Synonym: MENTAL RETARDATION, X-LINKED 108
 
Gene (location): SLC9A7 (Xp11.3)
 
Monarch Initiative: MONDO:0026723
OMIM®: 301024

Definition

X-linked intellectual developmental disorder-108 (MRX108) is characterized by early hypotonia, global developmental delay, and moderately to severely impaired intellectual development. Brisk tendon reflexes, variable facial dysmorphism, and fifth finger clinodactyly may be present (Khayat et al., 2019). [from OMIM]

Clinical features

From HPO
Pes planus
MedGen UID:
42034
Concept ID:
C0016202
Anatomical Abnormality
A foot where the longitudinal arch of the foot is in contact with the ground or floor when the individual is standing; or, in a patient lying supine, a foot where the arch is in contact with the surface of a flat board pressed against the sole of the foot by the examiner with a pressure similar to that expected from weight bearing; or, the height of the arch is reduced.
Clinodactyly of the 5th finger
MedGen UID:
340456
Concept ID:
C1850049
Congenital Abnormality
Clinodactyly refers to a bending or curvature of the fifth finger in the radial direction (i.e., towards the 4th finger).
Overweight
MedGen UID:
105424
Concept ID:
C0497406
Finding
Increased body weight with a body mass index of 25-29.9 kg per square meter.
Intellectual disability, moderate
MedGen UID:
7680
Concept ID:
C0026351
Mental or Behavioral Dysfunction
Moderate mental retardation is defined as an intelligence quotient (IQ) in the range of 35-49.
Babinski sign
MedGen UID:
19708
Concept ID:
C0034935
Finding
Upturning of the big toe (and sometimes fanning of the other toes) in response to stimulation of the sole of the foot. If the Babinski sign is present it can indicate damage to the corticospinal tract.
Delayed ability to walk
MedGen UID:
66034
Concept ID:
C0241726
Finding
A failure to achieve the ability to walk at an appropriate developmental stage. Most children learn to walk in a series of stages, and learn to walk short distances independently between 12 and 15 months.
Delayed speech and language development
MedGen UID:
105318
Concept ID:
C0454644
Finding
A degree of language development that is significantly below the norm for a child of a specified age.
Global developmental delay
MedGen UID:
107838
Concept ID:
C0557874
Finding
A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age.
Broad-based gait
MedGen UID:
167799
Concept ID:
C0856863
Finding
An abnormal gait pattern in which persons stand and walk with their feet spaced widely apart. This is often a component of cerebellar ataxia.
Attention deficit hyperactivity disorder
MedGen UID:
220387
Concept ID:
C1263846
Mental or Behavioral Dysfunction
Attention-deficit/hyperactivity disorder (ADHD) is a behavioral disorder that typically begins in childhood and is characterized by a short attention span (inattention), an inability to be calm and stay still (hyperactivity), and poor impulse control (impulsivity). Some people with ADHD have problems with only inattention or with hyperactivity and impulsivity, but most have problems related to all three features.\n\nIn people with ADHD, the characteristic behaviors are frequent and severe enough to interfere with the activities of daily living such as school, work, and relationships with others. Because of an inability to stay focused on tasks, people with inattention may be easily distracted, forgetful, avoid tasks that require sustained attention, have difficulty organizing tasks, or frequently lose items.\n\nIn most affected individuals, ADHD continues throughout life, but in about one-third of individuals, signs and symptoms of ADHD go away by adulthood.\n\nHyperactivity is usually shown by frequent movement. Individuals with this feature often fidget or tap their foot when seated, leave their seat when it is inappropriate to do so (such as in the classroom), or talk a lot and interrupt others.\n\nImpulsivity can result in hasty actions without thought for the consequences. Individuals with poor impulse control may have difficulty waiting for their turn, deferring to others, or considering their actions before acting.\n\nMore than two-thirds of all individuals with ADHD have additional conditions, including insomnia, mood or anxiety disorders, learning disorders, or substance use disorders. Affected individuals may also have autism spectrum disorder, which is characterized by impaired communication and social interaction, or Tourette syndrome, which is a disorder characterized by repetitive and involuntary movements or noises called tics.
Brisk reflexes
MedGen UID:
382164
Concept ID:
C2673700
Finding
Tendon reflexes that are noticeably more active than usual (conventionally denoted 3+ on clinical examination). Brisk reflexes may or may not indicate a neurological lesion. They are distinguished from hyperreflexia by the fact that hyerreflexia is characterized by hyperactive repeating (clonic) reflexes, which are considered to be always abnormal.
Delayed ability to sit
MedGen UID:
1368737
Concept ID:
C4476710
Finding
A failure to achieve the ability to sit at an appropriate developmental stage. Most children sit with support at 6 months of age and sit steadily without support at 9 months of age.
Hypotonia
MedGen UID:
10133
Concept ID:
C0026827
Finding
Hypotonia is an abnormally low muscle tone (the amount of tension or resistance to movement in a muscle). Even when relaxed, muscles have a continuous and passive partial contraction which provides some resistance to passive stretching. Hypotonia thus manifests as diminished resistance to passive stretching. Hypotonia is not the same as muscle weakness, although the two conditions can co-exist.
Muscle weakness
MedGen UID:
57735
Concept ID:
C0151786
Finding
Reduced strength of muscles.
Proximal muscle weakness
MedGen UID:
113169
Concept ID:
C0221629
Finding
A lack of strength of the proximal muscles.
Difficulty walking
MedGen UID:
86319
Concept ID:
C0311394
Finding
Reduced ability to walk (ambulate).
Generalized hypotonia
MedGen UID:
346841
Concept ID:
C1858120
Finding
Generalized muscular hypotonia (abnormally low muscle tone).
Drooling
MedGen UID:
8484
Concept ID:
C0013132
Finding
Habitual flow of saliva out of the mouth.
Myopathic facies
MedGen UID:
90695
Concept ID:
C0332615
Finding
A facial appearance characteristic of myopathic conditions. The face appears expressionless with sunken cheeks, bilateral ptosis, and inability to elevate the corners of the mouth, due to muscle weakness.
Downslanted palpebral fissures
MedGen UID:
98391
Concept ID:
C0423110
Finding
The palpebral fissure inclination is more than two standard deviations below the mean.
Long face
MedGen UID:
324419
Concept ID:
C1836047
Finding
Facial height (length) is more than 2 standard deviations above the mean (objective); or, an apparent increase in the height (length) of the face (subjective).
Midface retrusion
MedGen UID:
339938
Concept ID:
C1853242
Anatomical Abnormality
Posterior positions and/or vertical shortening of the infraorbital and perialar regions, or increased concavity of the face and/or reduced nasolabial angle.
Long philtrum
MedGen UID:
351278
Concept ID:
C1865014
Finding
Distance between nasal base and midline upper lip vermilion border more than 2 SD above the mean. Alternatively, an apparently increased distance between nasal base and midline upper lip vermilion border.
Thin upper lip vermilion
MedGen UID:
355352
Concept ID:
C1865017
Finding
Height of the vermilion of the upper lip in the midline more than 2 SD below the mean. Alternatively, an apparently reduced height of the vermilion of the upper lip in the frontal view (subjective).
High anterior hairline
MedGen UID:
477667
Concept ID:
C3276036
Finding
Distance between the hairline (trichion) and the glabella (the most prominent point on the frontal bone above the root of the nose), in the midline, more than two SD above the mean. Alternatively, an apparently increased distance between the hairline and the glabella.
Strabismus
MedGen UID:
21337
Concept ID:
C0038379
Disease or Syndrome
A misalignment of the eyes so that the visual axes deviate from bifoveal fixation. The classification of strabismus may be based on a number of features including the relative position of the eyes, whether the deviation is latent or manifest, intermittent or constant, concomitant or otherwise and according to the age of onset and the relevance of any associated refractive error.
Deeply set eye
MedGen UID:
473112
Concept ID:
C0423224
Finding
An eye that is more deeply recessed into the plane of the face than is typical.

Professional guidelines

PubMed

Ramirez Alcantara J, Grant NR, Sethuram S, Nagy A, Becker C, Sahai I, Stanley T, Halper A, Eichler FS
J Clin Endocrinol Metab 2023 Oct 18;108(11):e1306-e1315. doi: 10.1210/clinem/dgad286. PMID: 37220095Free PMC Article
Borchers J, Pukkala E, Mäkitie O, Laakso S
J Clin Endocrinol Metab 2023 Oct 18;108(11):2879-2885. doi: 10.1210/clinem/dgad283. PMID: 37216903Free PMC Article
Goldstein DS, Holmes CS, Kaler SG
Neurochem Res 2009 Aug;34(8):1464-8. Epub 2009 Feb 21 doi: 10.1007/s11064-009-9933-8. PMID: 19234788Free PMC Article

Recent clinical studies

Etiology

Ramirez Alcantara J, Grant NR, Sethuram S, Nagy A, Becker C, Sahai I, Stanley T, Halper A, Eichler FS
J Clin Endocrinol Metab 2023 Oct 18;108(11):e1306-e1315. doi: 10.1210/clinem/dgad286. PMID: 37220095Free PMC Article
Leonard H, Gold W, Samaco R, Sahin M, Benke T, Downs J
Orphanet J Rare Dis 2022 Mar 4;17(1):108. doi: 10.1186/s13023-022-02240-w. PMID: 35246185Free PMC Article
Vachalova I, Chandoga J, Petrovic R, Copikova-Cudrakova D, Sykora M, Traubner P
Bratisl Lek Listy 2007;108(10-11):462-6. PMID: 18306728
Demark JL, Feldman MA, Holden JJ
Am J Ment Retard 2003 Sep;108(5):314-26. doi: 10.1352/0895-8017(2003)108<314:BRBAAF>2.0.CO;2. PMID: 12901707
Loesch DZ, Lafranchi M, Scott D
Am J Med Genet 1988 May-Jun;30(1-2):149-64. doi: 10.1002/ajmg.1320300113. PMID: 3177440

Diagnosis

Ramirez Alcantara J, Grant NR, Sethuram S, Nagy A, Becker C, Sahai I, Stanley T, Halper A, Eichler FS
J Clin Endocrinol Metab 2023 Oct 18;108(11):e1306-e1315. doi: 10.1210/clinem/dgad286. PMID: 37220095Free PMC Article
Borchers J, Pukkala E, Mäkitie O, Laakso S
J Clin Endocrinol Metab 2023 Oct 18;108(11):2879-2885. doi: 10.1210/clinem/dgad283. PMID: 37216903Free PMC Article
Mak AS, Leung KY
Hong Kong Med J 2017 Apr;23(2):108-9. doi: 10.12809/hkmj175064. PMID: 28387201
Fehr S, Downs J, Ho G, de Klerk N, Forbes D, Christodoulou J, Williams S, Leonard H
Am J Med Genet A 2016 Nov;170(11):2860-2869. Epub 2016 Aug 16 doi: 10.1002/ajmg.a.37851. PMID: 27528505
Jedele KB
Semin Pediatr Neurol 2007 Sep;14(3):108-17. doi: 10.1016/j.spen.2007.07.002. PMID: 17980307

Therapy

Leonard H, Gold W, Samaco R, Sahin M, Benke T, Downs J
Orphanet J Rare Dis 2022 Mar 4;17(1):108. doi: 10.1186/s13023-022-02240-w. PMID: 35246185Free PMC Article
Marucha J, Lipiński P, Tylki-Szymańska A
Acta Biochim Pol 2022 Feb 28;69(1):251-255. doi: 10.18388/abp.2020_6071. PMID: 35226799
Tanaka H, Amano N, Tanaka K, Katsuki T, Adachi T, Shimozawa N, Kawai T
Endocr J 2020 Jun 29;67(6):655-658. Epub 2020 Feb 26 doi: 10.1507/endocrj.EJ19-0576. PMID: 32101828
Fu F, Liu HL, Li R, Han J, Yang X, Min P, Zhen L, Zhang YL, Xie GE, Lei TY, Li Y, Li J, Li DZ, Liao C
Gene 2014 Aug 10;546(2):222-5. Epub 2014 Jun 7 doi: 10.1016/j.gene.2014.06.012. PMID: 24914495
Loesch DZ, Lafranchi M, Scott D
Am J Med Genet 1988 May-Jun;30(1-2):149-64. doi: 10.1002/ajmg.1320300113. PMID: 3177440

Prognosis

Baker EK, Arora S, Amor DJ, Date P, Cross M, O'Brien J, Simons C, Rogers C, Goodall S, Slee J, Cahir C, Godler DE
J Autism Dev Disord 2023 Apr;53(4):1682-1692. Epub 2021 Jul 22 doi: 10.1007/s10803-021-05193-4. PMID: 34292487
Tanaka H, Amano N, Tanaka K, Katsuki T, Adachi T, Shimozawa N, Kawai T
Endocr J 2020 Jun 29;67(6):655-658. Epub 2020 Feb 26 doi: 10.1507/endocrj.EJ19-0576. PMID: 32101828
Iida A, Takano K, Takeshita E, Abe-Hatano C, Hirabayashi S, Inaba Y, Kosugi S, Kamatani Y, Momozawa Y, Kubo M, Nakagawa E, Inoue K, Goto YI
Cold Spring Harb Mol Case Stud 2019 Dec;5(6) Epub 2019 Dec 13 doi: 10.1101/mcs.a003988. PMID: 31444167Free PMC Article
Hatton DD, Hooper SR, Bailey DB, Skinner ML, Sullivan KM, Wheeler A
Am J Med Genet 2002 Mar 1;108(2):105-16. doi: 10.1002/ajmg.10216. PMID: 11857559
Hessl D, Dyer-Friedman J, Glaser B, Wisbeck J, Barajas RG, Taylor A, Reiss AL
Pediatrics 2001 Nov;108(5):E88. doi: 10.1542/peds.108.5.e88. PMID: 11694672

Clinical prediction guides

Iida A, Takano K, Takeshita E, Abe-Hatano C, Hirabayashi S, Inaba Y, Kosugi S, Kamatani Y, Momozawa Y, Kubo M, Nakagawa E, Inoue K, Goto YI
Cold Spring Harb Mol Case Stud 2019 Dec;5(6) Epub 2019 Dec 13 doi: 10.1101/mcs.a003988. PMID: 31444167Free PMC Article
O'Leary HM, Marschik PB, Khwaja OS, Ho E, Barnes KV, Clarkson TW, Bruck NM, Kaufmann WE
Dev Neurorehabil 2017 Feb;20(2):108-114. Epub 2015 Oct 12 doi: 10.3109/17518423.2015.1087437. PMID: 26457613
Ramos HE
Endocr Dev 2014;26:108-17. Epub 2014 Aug 29 doi: 10.1159/000363158. PMID: 25231447
Demark JL, Feldman MA, Holden JJ
Am J Ment Retard 2003 Sep;108(5):314-26. doi: 10.1352/0895-8017(2003)108<314:BRBAAF>2.0.CO;2. PMID: 12901707
Hatton DD, Hooper SR, Bailey DB, Skinner ML, Sullivan KM, Wheeler A
Am J Med Genet 2002 Mar 1;108(2):105-16. doi: 10.1002/ajmg.10216. PMID: 11857559

Supplemental Content

Table of contents

    Clinical resources

    Practice guidelines

    • PubMed
      See practice and clinical guidelines in PubMed. The search results may include broader topics and may not capture all published guidelines. See the FAQ for details.

    Consumer resources

    Recent activity

    Your browsing activity is empty.

    Activity recording is turned off.

    Turn recording back on

    See more...