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Intellectual developmental disorder, X-linked, syndromic, Hackmann-Di Donato type(MRXSHD)

MedGen UID:
1716269
Concept ID:
C5393302
Disease or Syndrome
Synonym: MENTAL RETARDATION, X-LINKED, WITH MARFANOID HABITUS, 2
 
Gene (location): NKAP (Xq24)
 
Monarch Initiative: MONDO:0026733
OMIM®: 301039

Definition

Hackmann-Di Donato-type X-linked syndromic intellectual developmental disorder (MRXSHD) is an X-linked recessive phenotype characterized by global developmental delay with hypotonia, delayed speech, and mildly delayed walking associated with somatic marfanoid features, including tall stature, long fingers, and mildly dysmorphic facies. Some patients may have cardiac defects, such as mitral valve regurgitation, as well as other anomalies related to connective tissue defects, such as scoliosis (summary by Fiordaliso et al., 2019). [from OMIM]

Clinical features

From HPO
Cryptorchidism
MedGen UID:
8192
Concept ID:
C0010417
Congenital Abnormality
Cryptorchidism, or failure of testicular descent, is a common human congenital abnormality with a multifactorial etiology that likely reflects the involvement of endocrine, environmental, and hereditary factors. Cryptorchidism can result in infertility and increases risk for testicular tumors. Testicular descent from abdomen to scrotum occurs in 2 distinct phases: the transabdominal phase and the inguinoscrotal phase (summary by Gorlov et al., 2002).
Arachnodactyly
MedGen UID:
2047
Concept ID:
C0003706
Congenital Abnormality
Abnormally long and slender fingers (spider fingers).
Clubfoot
MedGen UID:
3130
Concept ID:
C0009081
Congenital Abnormality
Clubfoot is a congenital limb deformity defined as fixation of the foot in cavus, adductus, varus, and equinus (i.e., inclined inwards, axially rotated outwards, and pointing downwards) with concomitant soft tissue abnormalities (Cardy et al., 2007). Clubfoot may occur in isolation or as part of a syndrome (e.g., diastrophic dysplasia, 222600). Clubfoot has been reported with deficiency of long bones and mirror-image polydactyly (Gurnett et al., 2008; Klopocki et al., 2012).
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.
Ventricular septal defect
MedGen UID:
42366
Concept ID:
C0018818
Congenital Abnormality
A hole between the two bottom chambers (ventricles) of the heart. The defect is centered around the most superior aspect of the ventricular septum.
Mitral regurgitation
MedGen UID:
7670
Concept ID:
C0026266
Disease or Syndrome
An abnormality of the mitral valve characterized by insufficiency or incompetence of the mitral valve resulting in retrograde leaking of blood through the mitral valve upon ventricular contraction.
Aortic root aneurysm
MedGen UID:
720712
Concept ID:
C1298820
Anatomical Abnormality
An abnormal localized widening (dilatation) of the aortic root.
Abdominal obesity
MedGen UID:
90229
Concept ID:
C0311277
Finding
Excessive fat around the stomach and abdomen.
Disproportionate tall stature
MedGen UID:
323048
Concept ID:
C1836996
Finding
A tall and slim body build with increased arm span to height ratio (>1.05) and a reduced upper-to-lower segment ratio (<0.85), i.e., unusually long arms and legs. The extremities as well as the hands and feet are unusually slim.
Protruding ear
MedGen UID:
343309
Concept ID:
C1855285
Finding
Angle formed by the plane of the ear and the mastoid bone greater than the 97th centile for age (objective); or, outer edge of the helix more than 2 cm from the mastoid at the point of maximum distance (objective).
Aggressive behavior
MedGen UID:
1375
Concept ID:
C0001807
Individual Behavior
Behavior or an act aimed at harming a person, animal, or physical property (e.g., acts of physical violence; shouting, swearing, and using harsh language; slashing someone's tires).
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.
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\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.\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.
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.
Scoliosis
MedGen UID:
11348
Concept ID:
C0036439
Disease or Syndrome
The presence of an abnormal lateral curvature of the spine.
Pectus carinatum
MedGen UID:
57643
Concept ID:
C0158731
Finding
A deformity of the chest caused by overgrowth of the ribs and characterized by protrusion of the sternum.
Camptodactyly
MedGen UID:
195780
Concept ID:
C0685409
Congenital Abnormality
The distal interphalangeal joint and/or the proximal interphalangeal joint of the fingers or toes cannot be extended to 180 degrees by either active or passive extension.
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.
Pectus excavatum
MedGen UID:
781174
Concept ID:
C2051831
Finding
A defect of the chest wall characterized by a depression of the sternum, giving the chest ("pectus") a caved-in ("excavatum") appearance.
Open mouth
MedGen UID:
116104
Concept ID:
C0240379
Finding
A facial appearance characterized by a permanently or nearly permanently opened mouth.
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.
Short philtrum
MedGen UID:
350006
Concept ID:
C1861324
Finding
Distance between nasal base and midline upper lip vermilion border more than 2 SD below the mean. Alternatively, an apparently decreased distance between nasal base and midline upper lip vermilion border.

Recent clinical studies

Diagnosis

Xu X, Gao C, Ye F, Peng A, Xu J, Jin K, Zhang J, Ye Y, Yang Y, Zhang X, Shen S, Jin F
J Cell Mol Med 2024 Apr;28(8):e18305. doi: 10.1111/jcmm.18305. PMID: 38647244Free PMC Article

Clinical prediction guides

Xu X, Gao C, Ye F, Peng A, Xu J, Jin K, Zhang J, Ye Y, Yang Y, Zhang X, Shen S, Jin F
J Cell Mol Med 2024 Apr;28(8):e18305. doi: 10.1111/jcmm.18305. PMID: 38647244Free PMC Article

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