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ZTTK syndrome(ZTTKS)

MedGen UID:
934663
Concept ID:
C4310696
Disease or Syndrome
Synonyms: ZHU-TOKITA-TAKENOUCHI-KIM SYNDROME; ZTTK MULTIPLE CONGENITAL ANOMALIES-MENTAL RETARDATION SYNDROME; ZTTKS
SNOMED CT: Brain malformations, musculoskeletal abnormalities, facial dysmorphism, intellectual disability syndrome (1169355000); Zhu Tokita Takenouchi Kim syndrome (1169355000); ZTTK syndrome (1169355000)
Modes of inheritance:
Autosomal dominant inheritance
MedGen UID:
141047
Concept ID:
C0443147
Intellectual Product
Source: Orphanet
A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in heterozygotes. In the context of medical genetics, an autosomal dominant disorder is caused when a single copy of the mutant allele is present. Males and females are affected equally, and can both transmit the disorder with a risk of 50% for each child of inheriting the mutant allele.
 
Gene (location): SON (21q22.11)
 
Monarch Initiative: MONDO:0014936
OMIM®: 617140
Orphanet: ORPHA500150

Definition

ZTTK syndrome (ZTTKS) is a severe multisystem developmental disorder characterized by delayed psychomotor development and intellectual disability. Affected individuals have characteristic dysmorphic facial features, hypotonia, poor feeding, poor overall growth, and eye or visual abnormalities. Most patients also have musculoskeletal abnormalities, and some have congenital defects of the heart and urogenital system. Brain imaging usually shows developmental abnormalities such as gyral changes, cortical and/or cerebellar atrophy, and thin corpus callosum (summary by Kim et al., 2016). [from OMIM]

Clinical features

From HPO
Polyuria
MedGen UID:
19404
Concept ID:
C0032617
Sign or Symptom
An increased rate of urine production.
Horseshoe kidney
MedGen UID:
65140
Concept ID:
C0221353
Congenital Abnormality
A connection of the right and left kidney by an isthmus of functioning renal parenchyma or fibrous tissue that crosses the midline.
Unilateral renal agenesis
MedGen UID:
75607
Concept ID:
C0266294
Congenital Abnormality
A unilateral form of agenesis of the kidney.
Small hand
MedGen UID:
108279
Concept ID:
C0575802
Finding
Disproportionately small hand.
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).
Aortic regurgitation
MedGen UID:
8153
Concept ID:
C0003504
Disease or Syndrome
An insufficiency of the aortic valve, leading to regurgitation (backward flow) of blood from the aorta into the left ventricle.
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.
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.
Fetal growth restriction
MedGen UID:
4693
Concept ID:
C0015934
Pathologic Function
An abnormal restriction of fetal growth with fetal weight below the tenth percentile for gestational age.
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).
Growth delay
MedGen UID:
99124
Concept ID:
C0456070
Pathologic Function
A deficiency or slowing down of growth pre- and postnatally.
Failure to thrive
MedGen UID:
746019
Concept ID:
C2315100
Disease or Syndrome
Failure to thrive (FTT) refers to a child whose physical growth is substantially below the norm.
Intestinal atresia
MedGen UID:
7129
Concept ID:
C0021828
Disease or Syndrome
An abnormal closure, or atresia of the tubular structure of the intestine.
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.
Isolated agenesis of gallbladder
MedGen UID:
82736
Concept ID:
C0266251
Congenital Abnormality
A developmental defect in which the gallbladder fails to form.
Chronic diarrhea
MedGen UID:
96036
Concept ID:
C0401151
Finding
The presence of chronic diarrhea, which is usually taken to mean diarrhea that has persisted for over 4 weeks.
Feeding difficulties in infancy
MedGen UID:
436211
Concept ID:
C2674608
Finding
Impaired feeding performance of an infant as manifested by difficulties such as weak and ineffective sucking, brief bursts of sucking, and falling asleep during sucking. There may be difficulties with chewing or maintaining attention.
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.
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).
Periventricular leukomalacia
MedGen UID:
6072
Concept ID:
C0023529
Disease or Syndrome
Periventricular leukomalacia is characterized by diffuse injury of deep cerebral white matter, accompanied in its most severe form by focal necrosis. The neuropathologic hallmarks of PVL are microglial activation and focal and diffuse periventricular depletion of premyelinating oligodendroglia.
Spasticity
MedGen UID:
7753
Concept ID:
C0026838
Sign or Symptom
A motor disorder characterized by a velocity-dependent increase in tonic stretch reflexes with increased muscle tone, exaggerated (hyperexcitable) tendon reflexes.
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.
Intellectual disability, severe
MedGen UID:
48638
Concept ID:
C0036857
Mental or Behavioral Dysfunction
Severe mental retardation is defined as an intelligence quotient (IQ) in the range of 20-34.
Status epilepticus
MedGen UID:
11586
Concept ID:
C0038220
Disease or Syndrome
Status epilepticus is a type of prolonged seizure resulting either from the failure of the mechanisms responsible for seizure termination or from the initiation of mechanisms which lead to abnormally prolonged seizures (after time point t1). It is a condition that can have long-term consequences (after time point t2), including neuronal death, neuronal injury, and alteration of neuronal networks, depending on the type and duration of seizures.
Arachnoid cyst
MedGen UID:
86860
Concept ID:
C0078981
Disease or Syndrome
An extra-parenchymal and intra-arachnoidal collection of fluid with a composition similar to that of cerebrospinal fluid.
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.
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.
Dysplastic corpus callosum
MedGen UID:
98128
Concept ID:
C0431369
Congenital Abnormality
Dysplasia and dysgenesis of the corpus callosum are nonspecific descriptions that imply defective development of the corpus callosum. The term dysplasia is applied when the morphology of the corpus callosum is altered as a congenital trait. For instance, the corpus callosum may be hump-shaped, kinked, or a striped corpus callosum that lacks an anatomically distinct genu and splenium.
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.
Autistic behavior
MedGen UID:
163547
Concept ID:
C0856975
Mental or Behavioral Dysfunction
Persistent deficits in social interaction and communication and interaction as well as a markedly restricted repertoire of activity and interest as well as repetitive patterns of behavior.
Abnormal cerebral white matter morphology
MedGen UID:
181756
Concept ID:
C0948163
Pathologic Function
An abnormality of the cerebral white matter.
Developmental regression
MedGen UID:
324613
Concept ID:
C1836830
Disease or Syndrome
Loss of developmental skills, as manifested by loss of developmental milestones.
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.
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.
Delayed ability to roll over
MedGen UID:
1718874
Concept ID:
C5397980
Finding
Delayed achievement of the ability to roll front to back and back to front.
Delayed ability to crawl
MedGen UID:
1772845
Concept ID:
C5421628
Finding
A failure to achieve the ability to crawl at an appropriate developmental stage. Normal infant motor development is marked by a series of postural milestones including learning to crawl on hands and knees between the ages of 6 and 10 months.
Craniosynostosis syndrome
MedGen UID:
1163
Concept ID:
C0010278
Disease or Syndrome
Craniosynostosis refers to the premature closure of the cranial sutures. Primary craniosynostosis refers to the closure of one or more sutures due to abnormalities in skull development, and secondary craniosynostosis results from failure of brain growth.
Kyphosis
MedGen UID:
44042
Concept ID:
C0022821
Anatomical Abnormality
Exaggerated anterior convexity of the thoracic vertebral column.
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.
Cervical rib
MedGen UID:
102359
Concept ID:
C0158779
Congenital Abnormality
Presence of rib formation in the cervical region.
Frontal bossing
MedGen UID:
67453
Concept ID:
C0221354
Congenital Abnormality
Bilateral bulging of the lateral frontal bone prominences with relative sparing of the midline.
Hypoplasia of the maxilla
MedGen UID:
66804
Concept ID:
C0240310
Congenital Abnormality
Abnormally small dimension of the Maxilla. Usually creating a malocclusion or malalignment between the upper and lower teeth or resulting in a deficient amount of projection of the base of the nose and lower midface region.
Hemivertebrae
MedGen UID:
82720
Concept ID:
C0265677
Congenital Abnormality
Absence of one half of the vertebral body.
Rib fusion
MedGen UID:
78570
Concept ID:
C0265695
Congenital Abnormality
Complete or partial merging of adjacent ribs.
Flexion contracture
MedGen UID:
83069
Concept ID:
C0333068
Anatomical Abnormality
A flexion contracture is a bent (flexed) joint that cannot be straightened actively or passively. It is thus a chronic loss of joint motion due to structural changes in muscle, tendons, ligaments, or skin that prevents normal movement of joints.
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.
Relative macrocephaly
MedGen UID:
338607
Concept ID:
C1849075
Congenital Abnormality
A relatively mild degree of macrocephaly in which the head circumference is not above two standard deviations from the mean, but appears dysproportionately large when other factors such as body stature are taken into account.
Macrocephaly
MedGen UID:
745757
Concept ID:
C2243051
Finding
Occipitofrontal (head) circumference greater than 97th centile compared to appropriate, age matched, sex-matched normal standards. Alternatively, a apparently increased size of the cranium.
Neonatal hypotonia
MedGen UID:
412209
Concept ID:
C2267233
Disease or Syndrome
Muscular hypotonia (abnormally low muscle tone) manifesting in the neonatal period.
Unilateral lung agenesis
MedGen UID:
909229
Concept ID:
C4082952
Congenital Abnormality
Lack of development of one lung.
Narrow mouth
MedGen UID:
44435
Concept ID:
C0026034
Congenital Abnormality
Distance between the commissures of the mouth more than 2 SD below the mean. Alternatively, an apparently decreased width of the oral aperture (subjective).
High palate
MedGen UID:
66814
Concept ID:
C0240635
Congenital Abnormality
Height of the palate more than 2 SD above the mean (objective) or palatal height at the level of the first permanent molar more than twice the height of the teeth (subjective).
Abnormality of the dentition
MedGen UID:
78084
Concept ID:
C0262444
Finding
Any abnormality of the teeth.
Downslanted palpebral fissures
MedGen UID:
98391
Concept ID:
C0423110
Finding
The palpebral fissure inclination is more than two standard deviations below the mean.
Submucous cleft hard palate
MedGen UID:
98472
Concept ID:
C0432103
Congenital Abnormality
Hard-palate submucous clefts are characterized by bony defects in the midline of the bony palate that are covered by the mucous membrane of the roof of the mouth. It may be possible to detect a submucous cleft hard palate upon palpation as a notch in the bony palate.
Thin vermilion border
MedGen UID:
108294
Concept ID:
C0578038
Finding
Height of the vermilion of the medial part of the lip more than 2 SD below the mean, or apparently reduced height of the vermilion of the lip in the frontal view. The vermilion is the red part of the lips (and confusingly, the vermilion itself is also often referred to as being equivalent the lips).
Epicanthus
MedGen UID:
151862
Concept ID:
C0678230
Congenital Abnormality
Epicanthus is a condition in which a fold of skin stretches from the upper to the lower eyelid, partially covering the inner canthus. Usher (1935) noted that epicanthus is a normal finding in the fetus of all races. Epicanthus also occurs in association with hereditary ptosis (110100).
Facial asymmetry
MedGen UID:
266298
Concept ID:
C1306710
Finding
An abnormal difference between the left and right sides of the face.
Sparse eyebrow
MedGen UID:
371332
Concept ID:
C1832446
Finding
Decreased density/number of eyebrow hairs.
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).
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 nose
MedGen UID:
343052
Concept ID:
C1854114
Finding
Distance from nasion to subnasale more than two standard deviations below the mean, or alternatively, an apparently decreased length from the nasal root to the nasal tip.
Broad eyebrow
MedGen UID:
344657
Concept ID:
C1856121
Finding
Regional increase in the width (height) of the eyebrow.
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.
Downturned corners of mouth
MedGen UID:
356471
Concept ID:
C1866195
Anatomical Abnormality
A morphological abnormality of the mouth in which the angle of the mouth is downturned. The oral commissures are positioned inferior to the midline labial fissure.
Full cheeks
MedGen UID:
355661
Concept ID:
C1866231
Finding
Increased prominence or roundness of soft tissues between zygomata and mandible.
Bifid uvula
MedGen UID:
1646931
Concept ID:
C4551488
Congenital Abnormality
Uvula separated into two parts most easily seen at the tip.
Hyperextensible skin
MedGen UID:
66023
Concept ID:
C0241074
Finding
A condition in which the skin can be stretched beyond normal, and then returns to its initial position.
Curly hair
MedGen UID:
488919
Concept ID:
C0558165
Finding
Breech presentation
MedGen UID:
654
Concept ID:
C0006157
Pathologic Function
A position of the fetus at delivery in which the fetus enters the birth canal with the buttocks or feet first.
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.
Optic atrophy
MedGen UID:
18180
Concept ID:
C0029124
Disease or Syndrome
Atrophy of the optic nerve. Optic atrophy results from the death of the retinal ganglion cell axons that comprise the optic nerve and manifesting as a pale optic nerve on fundoscopy.
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.
Cerebral visual impairment
MedGen UID:
890568
Concept ID:
C4048268
Pathologic Function
A form of loss of vision caused by damage to the visual cortex rather than a defect in the eye.

Term Hierarchy

CClinical test,  RResearch test,  OOMIM,  GGeneReviews,  VClinVar  
  • CROGVZTTK syndrome

Recent clinical studies

Etiology

Yi Z, Song Z, Li F, Yang C, Xue J, Li L, Zhang M, Zhang Y
Int J Dev Neurosci 2022 May;82(3):271-276. Epub 2022 Feb 3 doi: 10.1002/jdn.10170. PMID: 35080253

Diagnosis

Pasca L, Politano D, Cavallini A, Panzeri E, Vigone MC, Baldoli C, Abbate M, Kullmann G, Marelli S, Pozzobon G, Vincenzi G, Nacinovich R, Bassi MT, Romaniello R
Neuropediatrics 2024 Jun;55(3):191-195. Epub 2023 Jun 21 doi: 10.1055/a-2114-4387. PMID: 37343586
Pietrobattista A, Della Volpe L, Francalanci P, Figà Talamanca L, Monti L, Lepri FR, Basso MS, Liccardo D, Della Corte C, Mosca A, Alterio T, Veraldi S, Callea F, Novelli A, Maggiore G
Genes (Basel) 2023 Mar 17;14(3) doi: 10.3390/genes14030739. PMID: 36981010Free PMC Article
Kushary ST, Revah-Politi A, Barua S, Ganapathi M, Accogli A, Aggarwal V, Brunetti-Pierri N, Cappuccio G, Capra V, Fagerberg CR, Gazdagh G, Guzman E, Hadonou M, Harrison V, Havelund K, Iancu D, Kraus A, Lippa NC, Mansukhani M, McBrian D, McEntagart M, Pacio-Míguez M, Palomares-Bralo M, Pottinger C, Ruivenkamp CAL, Sacco O, Santen GWE, Santos-Simarro F, Scala M, Short J, Sørensen KP, Woods CG; DDD Study; TUDP Consortium, Anyane Yeboa K
Am J Med Genet A 2021 Dec;185(12):3740-3753. Epub 2021 Jul 31 doi: 10.1002/ajmg.a.62445. PMID: 34331327Free PMC Article
Yang L, Yang F
Mol Genet Genomic Med 2020 Nov;8(11):e1496. Epub 2020 Sep 14 doi: 10.1002/mgg3.1496. PMID: 32926520Free PMC Article
Slezak R, Smigiel R, Rydzanicz M, Pollak A, Kosinska J, Stawinski P, Malgorzata Sasiadek M, Ploski R
Mol Genet Genomic Med 2020 Oct;8(10):e1432. Epub 2020 Jul 24 doi: 10.1002/mgg3.1432. PMID: 32705777Free PMC Article

Prognosis

Pasca L, Politano D, Cavallini A, Panzeri E, Vigone MC, Baldoli C, Abbate M, Kullmann G, Marelli S, Pozzobon G, Vincenzi G, Nacinovich R, Bassi MT, Romaniello R
Neuropediatrics 2024 Jun;55(3):191-195. Epub 2023 Jun 21 doi: 10.1055/a-2114-4387. PMID: 37343586

Clinical prediction guides

Vukadin L, Park B, Mohamed M, Li H, Elkholy A, Torrelli-Diljohn A, Kim JH, Jeong K, Murphy JM, Harvey CA, Dunlap S, Gehrs L, Lee H, Kim HG, Sah JP, Lee SN, Stanford D, Barrington RA, Foote JB, Sorace AG, Welner RS, Hildreth BE 3rd, Lim SS, Ahn EE
JCI Insight 2024 Mar 8;9(5) doi: 10.1172/jci.insight.175053. PMID: 38290089Free PMC Article
Pasca L, Politano D, Cavallini A, Panzeri E, Vigone MC, Baldoli C, Abbate M, Kullmann G, Marelli S, Pozzobon G, Vincenzi G, Nacinovich R, Bassi MT, Romaniello R
Neuropediatrics 2024 Jun;55(3):191-195. Epub 2023 Jun 21 doi: 10.1055/a-2114-4387. PMID: 37343586
Dingemans AJM, Truijen KMG, Kim JH, Alaçam Z, Faivre L, Collins KM, Gerkes EH, van Haelst M, van de Laar IMBH, Lindstrom K, Nizon M, Pauling J, Heropolitańska-Pliszka E, Plomp AS, Racine C, Sachdev R, Sinnema M, Skranes J, Veenstra-Knol HE, Verberne EA, Vulto-van Silfhout AT, Wilsterman MEF, Ahn EE, de Vries BBA, Vissers LELM
Eur J Hum Genet 2022 Mar;30(3):271-281. Epub 2021 Sep 15 doi: 10.1038/s41431-021-00960-4. PMID: 34521999Free PMC Article
Slezak R, Smigiel R, Rydzanicz M, Pollak A, Kosinska J, Stawinski P, Malgorzata Sasiadek M, Ploski R
Mol Genet Genomic Med 2020 Oct;8(10):e1432. Epub 2020 Jul 24 doi: 10.1002/mgg3.1432. PMID: 32705777Free PMC Article

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