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Intellectual disability, X-linked 99, syndromic, female-restricted(MRXS99F)

MedGen UID:
899839
Concept ID:
C4225416
Disease or Syndrome
Synonyms: INTELLECTUAL DEVELOPMENTAL DISORDER, X-LINKED 99, SYNDROMIC, FEMALE-RESTRICTED; MRXS99F
 
Gene (location): USP9X (Xp11.4)
 
Monarch Initiative: MONDO:0010502
OMIM®: 300968

Definition

Female-restricted X-linked syndromic intellectual developmental disorder-99 (MRXS99F) is an X-linked dominant neurodevelopmental disorder characterized by delayed psychomotor development and mild to moderate intellectual disability. Affected females can have a wide range of additional congenital anomalies, including scoliosis, postaxial polydactyly, mild cardiac or urogenital anomalies, dysmorphic facial features, and mild structural brain abnormalities (summary by Reijnders et al., 2016). [from OMIM]

Clinical features

From HPO
Hydronephrosis
MedGen UID:
42531
Concept ID:
C0020295
Disease or Syndrome
Severe distention of the kidney with dilation of the renal pelvis and calices.
Renal dysplasia
MedGen UID:
760690
Concept ID:
C3536714
Congenital Abnormality
The presence of developmental dysplasia of the kidney.
Postaxial polydactyly
MedGen UID:
67394
Concept ID:
C0220697
Congenital Abnormality
Polydactyly refers to the occurrence of supernumerary digits and is the most frequent of congenital hand and foot deformities. Based on the location of the extra digits, polydactyly can be classified into preaxial, involving the thumb or great toe; postaxial, affecting the fifth digit; and central, involving the 3 central digits. Postaxial polydactyly (PAP) is further subclassified into 2 types: in type A, a well-formed extra digit articulates with the fifth or a sixth metacarpal, whereas in type B, a rudimentary, poorly developed extra digit is present (summary by Umm-e-Kalsoom et al., 2012). Genetic Heterogeneity of Postaxial Polydactyly Other forms of postaxial polydactyly type A include PAPA2 (602085) on chromosome 13q21; PAPA3 (607324) on chromosome 19p13; PAPA4 (608562) on chromosome 7q22; PAPA5 (263450) on chromosome 13q13; PAPA6 (615226), caused by mutation in the ZNF141 gene (194648) on chromosome 4p16; PAPA7 (617642), caused by mutation in the IQCE gene (617631) on chromosome 7p22; PAPA8 (618123), caused by mutation in the GLI1 gene (165220) on chromosome 12q13; PAPA9 (618219), caused by mutation in the CIBAR1 gene (617273) on chromosome 8q22; and PAPA10 (618498), caused by mutation in the KIAA0825 gene (617266) on chromosome 5q15.
Tapered finger
MedGen UID:
98098
Concept ID:
C0426886
Finding
The gradual reduction in girth of the finger from proximal to distal.
Small hand
MedGen UID:
108279
Concept ID:
C0575802
Finding
Disproportionately small hand.
Pes cavus
MedGen UID:
675590
Concept ID:
C0728829
Congenital Abnormality
An increase in height of the medial longitudinal arch of the foot that does not flatten on weight bearing (i.e., a distinctly hollow form of the sole of the foot when it is bearing weight).
Short foot
MedGen UID:
376415
Concept ID:
C1848673
Finding
A measured foot length that is more than 2 SD below the mean for a newborn of 27 - 41 weeks gestation, or foot that is less than the 3rd centile for individuals from birth to 16 years of age (objective). Alternatively, a foot that appears disproportionately short (subjective).
Patent ductus arteriosus
MedGen UID:
4415
Concept ID:
C0013274
Congenital Abnormality
In utero, the ductus arteriosus (DA) serves to divert ventricular output away from the lungs and toward the placenta by connecting the main pulmonary artery to the descending aorta. A patent ductus arteriosus (PDA) in the first 3 days of life is a physiologic shunt in healthy term and preterm newborn infants, and normally is substantially closed within about 24 hours after bith and completely closed after about three weeks. Failure of physiologcal closure is referred to a persistent or patent ductus arteriosus (PDA). Depending on the degree of left-to-right shunting, PDA can have clinical consequences.
Atrial septal defect
MedGen UID:
6753
Concept ID:
C0018817
Congenital Abnormality
Atrial septal defect (ASD) is a congenital abnormality of the interatrial septum that enables blood flow between the left and right atria via the interatrial septum.
Lower limb asymmetry
MedGen UID:
44089
Concept ID:
C0023221
Finding
A difference in length or diameter between the left and right leg.
Short stature
MedGen UID:
87607
Concept ID:
C0349588
Finding
A height below that which is expected according to age and gender norms. Although there is no universally accepted definition of short stature, many refer to "short stature" as height more than 2 standard deviations below the mean for age and gender (or below the 3rd percentile for age and gender dependent norms).
Imperforate anus
MedGen UID:
1997
Concept ID:
C0003466
Congenital Abnormality
Congenital absence of the anus, i.e., the opening at the bottom end of the intestinal tract.
Feeding difficulties
MedGen UID:
65429
Concept ID:
C0232466
Finding
Impaired ability to eat related to problems gathering food and getting ready to suck, chew, or swallow it.
Low-set ears
MedGen UID:
65980
Concept ID:
C0239234
Congenital Abnormality
Upper insertion of the ear to the scalp below an imaginary horizontal line drawn between the inner canthi of the eye and extending posteriorly to the ear.
Posteriorly rotated ears
MedGen UID:
96566
Concept ID:
C0431478
Congenital Abnormality
A type of abnormal location of the ears in which the position of the ears is characterized by posterior rotation (the superior part of the ears is rotated towards the back of the head, and the inferior part of the ears towards the front).
Hearing impairment
MedGen UID:
235586
Concept ID:
C1384666
Disease or Syndrome
A decreased magnitude of the sensory perception of sound.
Seizure
MedGen UID:
20693
Concept ID:
C0036572
Sign or Symptom
A seizure is an intermittent abnormality of nervous system physiology characterized by a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain.
Cerebellar hypoplasia
MedGen UID:
120578
Concept ID:
C0266470
Congenital Abnormality
Cerebellar hypoplasia is a descriptive term implying a cerebellum with a reduced volume, but a normal shape and is stable over time.
Hypoplasia of the corpus callosum
MedGen UID:
138005
Concept ID:
C0344482
Congenital Abnormality
Underdevelopment of the corpus callosum.
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.
Abnormal cortical gyration
MedGen UID:
343457
Concept ID:
C1856019
Anatomical Abnormality
An abnormality of the gyri (i.e., the ridges) of the cerebral cortex of the brain.
Ventriculomegaly
MedGen UID:
480553
Concept ID:
C3278923
Finding
An increase in size of the ventricular system of the brain.
Intellectual disability
MedGen UID:
811461
Concept ID:
C3714756
Mental or Behavioral Dysfunction
Intellectual disability, previously referred to as mental retardation, is characterized by subnormal intellectual functioning that occurs during the developmental period. It is defined by an IQ score below 70.
Hip dislocation
MedGen UID:
42455
Concept ID:
C0019554
Injury or Poisoning
Displacement of the femur from its normal location in the hip joint.
Scoliosis
MedGen UID:
11348
Concept ID:
C0036439
Disease or Syndrome
The presence of an abnormal lateral curvature of the spine.
Brachycephaly
MedGen UID:
113165
Concept ID:
C0221356
Congenital Abnormality
An abnormality of skull shape characterized by a decreased anterior-posterior diameter. That is, a cephalic index greater than 81%. Alternatively, an apparently shortened anteroposterior dimension (length) of the head compared to width.
Joint hypermobility
MedGen UID:
336793
Concept ID:
C1844820
Finding
The capability that a joint (or a group of joints) has to move, passively and/or actively, beyond normal limits along physiological axes.
Generalized hypotonia
MedGen UID:
346841
Concept ID:
C1858120
Finding
Generalized muscular hypotonia (abnormally low muscle tone).
Dandy-Walker malformation
MedGen UID:
419183
Concept ID:
C2931867
Congenital Abnormality
A congenital brain malformation typically characterized by incomplete formation of the cerebellar vermis, dilation of the fourth ventricle, and enlargement of the posterior fossa. In layman's terms, Dandy Walker malformation is a cyst in the cerebellum (typically symmetrical) that is involved with the fourth ventricle. This may interfere with the ability to drain cerebrospinal fluid from the brain, resulting in hydrocephalus. Dandy Walker cysts are formed during early embryonic development, while the brain forms. The cyst in the cerebellum typically has several blood vessels running through it connecting to the brain, thereby prohibiting surgical removal.
Developmental dysplasia of the hip
MedGen UID:
1640560
Concept ID:
C4551649
Congenital Abnormality
Congenital dysplasia of the hip (CDH) is an abnormality of the seating of the femoral head in the acetabulum. Its severity ranges from mild instability of the femoral head with slight capsular laxity, through moderate lateral displacement of the femoral head, without loss of contact of the head with the acetabulum, up to complete dislocation of the femoral head from the acetabulum. It is one of the most common skeletal congenital anomalies (summary by Sollazzo et al., 2000). Acetabular dysplasia is an idiopathic, localized developmental dysplasia of the hip that is characterized by a shallow hip socket and decreased coverage of the femoral head. Its radiologic criteria include the center-edge angle of Wiberg, the Sharp angle, and the acetabular roof obliquity. Most patients with acetabular dysplasia develop osteoarthritis (165720) after midlife, and even mild acetabular dysplasia can cause hip osteoarthritis (summary by Mabuchi et al., 2006). CDH occurs as an isolated anomaly or with more general disorders represented by several syndromes and with chromosomal abnormalities such as trisomy 18 (Wynne-Davies, 1970). Genetic Heterogeneity of Developmental Dysplasia of the Hip Developmental dysplasia of the hip-1 (DDH1) maps to chromosome 13q22; DDH2 (615612) maps to chromosome 3p21. DDH3 (620690) is caused by mutation in the LRP1 gene (107770) on chromosome 12q13.
Respiratory distress
MedGen UID:
96907
Concept ID:
C0476273
Sign or Symptom
Respiratory distress is objectively observable as the physical or emotional consequences from the experience of dyspnea. The physical presentation of respiratory distress is generally referred to as labored breathing, while the sensation of respiratory distress is called shortness of breath or dyspnea.
Recurrent respiratory infections
MedGen UID:
812812
Concept ID:
C3806482
Finding
An increased susceptibility to respiratory infections as manifested by a history of recurrent respiratory infections.
Choanal atresia
MedGen UID:
3395
Concept ID:
C0008297
Congenital Abnormality
Absence or abnormal closure of the choana (the posterior nasal aperture). Most embryologists believe that posterior choanal atresia results from a failure of rupture between the 35th and 38th day of fetal life of the partition which separates the bucconasal or buccopharyngeal membranes. The resultant choanal atresia may be unilateral or bilateral, bony or membranous, complete or incomplete. In over 90 per cent of cases the obstruction is bony, while in the remainder it is membranous. The bony type of atresia is commonly located 1-2 mm. anterior to the posterior edge of the hard palate, and the osseous septum varies in thickness from 1 to 10 mm. In the membranous form of choanal atresia the obstruction usually occurs further posteriorly. In approximately one third of cases the atresia is bilateral.
Bulbous nose
MedGen UID:
66013
Concept ID:
C0240543
Finding
Increased volume and globular shape of the anteroinferior aspect of the nose.
Abnormality of the dentition
MedGen UID:
78084
Concept ID:
C0262444
Finding
Any abnormality of the teeth.
Short palpebral fissure
MedGen UID:
98067
Concept ID:
C0423112
Finding
Distance between the medial and lateral canthi is more than 2 SD below the mean for age (objective); or, apparently reduced length of the palpebral fissures.
Prominent nose
MedGen UID:
98423
Concept ID:
C0426415
Finding
Distance between subnasale and pronasale more than two standard deviations above the mean, or alternatively, an apparently increased anterior protrusion of the nasal tip.
Smooth philtrum
MedGen UID:
222980
Concept ID:
C1142533
Finding
Flat skin surface, with no ridge formation in the central region of the upper lip between the nasal base and upper vermilion border.
Facial asymmetry
MedGen UID:
266298
Concept ID:
C1306710
Finding
An abnormal difference between the left and right sides of the face.
Depressed nasal bridge
MedGen UID:
373112
Concept ID:
C1836542
Finding
Posterior positioning of the nasal root in relation to the overall facial profile for age.
Prominent forehead
MedGen UID:
373291
Concept ID:
C1837260
Finding
Forward prominence of the entire forehead, due to protrusion of the frontal bone.
Narrow forehead
MedGen UID:
326956
Concept ID:
C1839758
Finding
Width of the forehead or distance between the frontotemporales is more than two standard deviations below the mean (objective); or apparently narrow intertemporal region (subjective).
Wide nasal bridge
MedGen UID:
341441
Concept ID:
C1849367
Finding
Increased breadth of the nasal bridge (and with it, the nasal root).
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.
Cleft palate
MedGen UID:
756015
Concept ID:
C2981150
Congenital Abnormality
Cleft palate is a developmental defect of the palate resulting from a failure of fusion of the palatine processes and manifesting as a separation of the roof of the mouth (soft and hard palate).
Bifid uvula
MedGen UID:
1646931
Concept ID:
C4551488
Congenital Abnormality
Uvula separated into two parts most easily seen at the tip.
Hypertrichosis
MedGen UID:
43787
Concept ID:
C0020555
Disease or Syndrome
Hypertrichosis is increased hair growth that is abnormal in quantity or location.
Sacral dimple
MedGen UID:
98428
Concept ID:
C0426848
Finding
A cutaneous indentation resulting from tethering of the skin to underlying structures (bone) of the intergluteal cleft.
Abnormality of thyroid physiology
MedGen UID:
808233
Concept ID:
C0857576
Finding
An abnormal functionality of the thyroid gland.
Unilateral breast hypoplasia
MedGen UID:
335016
Concept ID:
C1844722
Finding
Underdevelopment of the breast on one side only.
Astigmatism
MedGen UID:
2473
Concept ID:
C0004106
Disease or Syndrome
Astigmatism (from the Greek 'a' meaning absence and 'stigma' meaning point) is a condition in which the parallel rays of light entering the eye through the refractive media are not focused on a single point. Both corneal and noncorneal factors contribute to refractive astigmatism. Corneal astigmatism is mainly the result of an aspheric anterior surface of the cornea, which can be measured readily by means of a keratometer; in a small fraction of cases (approximately 1 in 10) the effect is neutralized by the back surface. The curvature of the back surface of the cornea is not considered in most studies, because it is more difficult to measure; moreover, in the case of severe corneal astigmatism, there is evidence that both surfaces have the same configuration. Noncorneal factors are errors in the curvature of the 2 surfaces of the crystalline lens, irregularity in the refractive index of the lens, and an eccentric lens position. Since the cornea is the dominant component of the eye's refracting system, a highly astigmatic cornea is likely to result in a similarly astigmatic ocular refraction (summary by Clementi et al., 1998).
Hypermetropia
MedGen UID:
43780
Concept ID:
C0020490
Disease or Syndrome
An abnormality of refraction characterized by the ability to see objects in the distance clearly, while objects nearby appear blurry.
Myopia
MedGen UID:
44558
Concept ID:
C0027092
Disease or Syndrome
Nearsightedness, also known as myopia, is an eye condition that causes blurry distance vision. People who are nearsighted have more trouble seeing things that are far away (such as when driving) than things that are close up (such as when reading or using a computer). If it is not treated with corrective lenses or surgery, nearsightedness can lead to squinting, eyestrain, headaches, and significant visual impairment.\n\nNearsightedness usually begins in childhood or adolescence. It tends to worsen with age until adulthood, when it may stop getting worse (stabilize). In some people, nearsightedness improves in later adulthood.\n\nFor normal vision, light passes through the clear cornea at the front of the eye and is focused by the lens onto the surface of the retina, which is the lining of the back of the eye that contains light-sensing cells. People who are nearsighted typically have eyeballs that are too long from front to back. As a result, light entering the eye is focused too far forward, in front of the retina instead of on its surface. It is this change that causes distant objects to appear blurry. The longer the eyeball is, the farther forward light rays will be focused and the more severely nearsighted a person will be.\n\nNearsightedness is measured by how powerful a lens must be to correct it. The standard unit of lens power is called a diopter. Negative (minus) powered lenses are used to correct nearsightedness. The more severe a person's nearsightedness, the larger the number of diopters required for correction. In an individual with nearsightedness, one eye may be more nearsighted than the other.\n\nEye doctors often refer to nearsightedness less than -5 or -6 diopters as "common myopia." Nearsightedness of -6 diopters or more is commonly called "high myopia." This distinction is important because high myopia increases a person's risk of developing other eye problems that can lead to permanent vision loss or blindness. These problems include tearing and detachment of the retina, clouding of the lens (cataract), and an eye disease called glaucoma that is usually related to increased pressure within the eye. The risk of these other eye problems increases with the severity of the nearsightedness. The term "pathological myopia" is used to describe cases in which high myopia leads to tissue damage within the eye.
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.
Cataract
MedGen UID:
39462
Concept ID:
C0086543
Disease or Syndrome
A cataract is an opacity or clouding that develops in the crystalline lens of the eye or in its capsule.
Hypotelorism
MedGen UID:
96107
Concept ID:
C0424711
Finding
Interpupillary distance less than 2 SD below the mean (alternatively, the appearance of an decreased interpupillary distance or closely spaced eyes).

Recent clinical studies

Etiology

Sisoudiya SD, Mishra P, Li H, Schraw JM, Scheurer ME, Salvi S, Doddapaneni H, Muzny D, Mitchell D, Taylor O, Sabo A, Lupo PJ, Plon SE
Blood Adv 2023 Aug 22;7(16):4563-4575. doi: 10.1182/bloodadvances.2023009814. PMID: 37289514Free PMC Article

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