microcephalic primordial dwarfism due to RTTN deficiency

MONDO:0018764Mondo

Findings

No curated finding names microcephalic primordial dwarfism due to RTTN deficiency yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.

Microcephalic primordial dwarfism due to RTTN deficiency is a rare, genetic, multiple congenital anomalies/dysmorphic syndrome characterized by primary microcephaly, profound short stature, moderate to severe intellectual disability, global developmental delay, craniofacial dysmorphism (e.g. sloping forehead, high and broad nasal bridge) and variable brain malformations, including simplified gyration, pachygyria, polymicrogyria, reduced sulcation, dysgenesis of corpus callosum and deformed ventricles. Renal anomalies, bilateral hearing loss, multiple joint contractures, severe failure to thrive and a sacral lesion cephalad to the gluteal crease have also been reported.

Definition from the Mondo Disease Ontology (MONDO:0018764), read 2026-09-29. CC BY 4.0.

Inheritance: Autosomal recessive inheritance

Features

81 features

What the disease is reported to present with, and how often among people who have it — never how often a feature means the disease. HPO, annotations 2026-09-02.

Abnormal pyramidal signHPOHP:0007256
- 2 of 2 reported patients
- Occasional (5% to 29% of cases)
Decreased body weightHPOHP:0004325
- 6 of 6 reported patients
EEG abnormalityHPOHP:0002353
- 2 of 2 reported patients
MicrocephalyHPOHP:0000252
- 6 of 6 reported patients
- Very frequent (80% to 99% of cases)
SeizureHPOHP:0001250
- 4 of 4 reported patients
- Occasional (5% to 29% of cases)

Genes

1 gene

Germline variants in the gene encoding each protein, as classified by GenCC submitters, each in their own words. Limited, disputed and refuted submissions are listed too.

RTTNHGNC:18654
- Definitive · ClinGen · Autosomal recessive · 2024
- Definitive · G2P · Autosomal recessive · 2018
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal recessive · 2019
- Strong · PanelApp Australia · Autosomal recessive · 2025
- Supportive · Orphanet · Autosomal recessive · 2021

Where it sits

A kind of: primordial dwarfism and slender bone disorder
syndromic disease
Narrower terms (1): bilateral generalized polymicrogyria

Show the remaining 69

Severe global developmental delayHPOHP:0011344
- Frequent (30% to 79% of cases)
Severe intellectual disabilityHPOHP:0010864
- Frequent (30% to 79% of cases)
Severe short statureHPOHP:0003510
- Frequent (30% to 79% of cases)
Sloping foreheadHPOHP:0000340
- Frequent (30% to 79% of cases)
VentriculomegalyHPOHP:0002119
- Frequent (30% to 79% of cases)
DysarthriaHPOHP:0001260
- 2 of 4 reported patients
- Occasional (5% to 29% of cases)
2-5 finger cutaneous syndactylyHPOHP:0005650
- Occasional (5% to 29% of cases)
4-5 finger cutaneous syndactylyHPOHP:0010705
- Occasional (5% to 29% of cases)
Abnormal occipital bone morphologyHPOHP:0012294
- Occasional (5% to 29% of cases)
Abnormal periventricular white matter morphologyHPOHP:0002518
- Occasional (5% to 29% of cases)
Abnormal renal collecting system morphologyHPOHP:0004742
- Occasional (5% to 29% of cases)
Abnormality of the orbital regionHPOHP:0000315
- Occasional (5% to 29% of cases)
Agenesis of corpus callosumHPOHP:0001274
- 1 of 6 reported patients · Congenital onset
- Occasional (5% to 29% of cases)
Ankle flexion contractureHPOHP:0006466
- Occasional (5% to 29% of cases)
Arachnoid cystHPOHP:0100702
- Occasional (5% to 29% of cases)
Attenuation of retinal blood vesselsHPOHP:0007843
- Occasional (5% to 29% of cases)
Axial hypotoniaHPOHP:0008936
- Occasional (5% to 29% of cases)
Bilateral microphthalmosHPOHP:0007633
- Occasional (5% to 29% of cases)
Bilateral sensorineural hearing impairmentHPOHP:0008619
- Occasional (5% to 29% of cases)
Camptodactyly of fingerHPOHP:0100490
- Occasional (5% to 29% of cases)
Cerebellar atrophyHPOHP:0001272
- 1 of 3 reported patients
- Occasional (5% to 29% of cases)
Cerebellar hypoplasiaHPOHP:0001321
- Occasional (5% to 29% of cases)
Cerebral atrophyHPOHP:0002059
- Occasional (5% to 29% of cases)
Cerebral hypoplasiaHPOHP:0006872
- Occasional (5% to 29% of cases)
Cortical dysplasiaHPOHP:0002539
- Occasional (5% to 29% of cases)
CraniosynostosisHPOHP:0001363
- Occasional (5% to 29% of cases)
CryptorchidismHPOHP:0000028
- Occasional (5% to 29% of cases)
Duodenal atresiaHPOHP:0002247
- Occasional (5% to 29% of cases)
Eczematoid dermatitisHPOHP:0000964
- Occasional (5% to 29% of cases)
Hyperkinetic movementsHPOHP:0002487
- Occasional (5% to 29% of cases)
HypertoniaHPOHP:0001276
- Occasional (5% to 29% of cases)
Hypoplasia of the corpus callosumHPOHP:0002079
- Occasional (5% to 29% of cases)
Hypoplasia of the frontal lobesHPOHP:0007333
- Occasional (5% to 29% of cases)
Hypoplasia of the ponsHPOHP:0012110
- Occasional (5% to 29% of cases)
HypospadiasHPOHP:0000047
- Occasional (5% to 29% of cases)
HypotelorismHPOHP:0000601
- Occasional (5% to 29% of cases)
Knee flexion contractureHPOHP:0006380
- Occasional (5% to 29% of cases)
LissencephalyHPOHP:0001339
- 1 of 6 reported patients
- Occasional (5% to 29% of cases)
Lobar holoprosencephalyHPOHP:0006870
- Occasional (5% to 29% of cases)
MicrophallusHPOHP:0030260
- Occasional (5% to 29% of cases)
MicroretrognathiaHPOHP:0000308
- Occasional (5% to 29% of cases)
Motor stereotypyHPOHP:0000733
- Occasional (5% to 29% of cases)
Narrow mouthHPOHP:0000160
- Occasional (5% to 29% of cases)
Olivopontocerebellar hypoplasiaHPOHP:0006955
- Occasional (5% to 29% of cases)
Optic disc pallorHPOHP:0000543
- Occasional (5% to 29% of cases)
Optic nerve hypoplasiaHPOHP:0000609
- Occasional (5% to 29% of cases)
PachygyriaHPOHP:0001302
- Occasional (5% to 29% of cases)
Pelvic kidneyHPOHP:0000125
- Occasional (5% to 29% of cases)
Periventricular heterotopiaHPOHP:0007165
- Occasional (5% to 29% of cases)
Posteriorly rotated earsHPOHP:0000358
- Occasional (5% to 29% of cases)
Prominent metopic ridgeHPOHP:0005487
- Occasional (5% to 29% of cases)
Prominent nasal bridgeHPOHP:0000426
- Occasional (5% to 29% of cases)
ProptosisHPOHP:0000520
- Occasional (5% to 29% of cases)
RetrognathiaHPOHP:0000278
- Occasional (5% to 29% of cases)
Sacrococcygeal pilonidal abnormalityHPOHP:0010767
- Occasional (5% to 29% of cases)
Self-injurious behaviorHPOHP:0100716
- Occasional (5% to 29% of cases)
Simplified gyral patternHPOHP:0009879
- Occasional (5% to 29% of cases)
Sleep disturbanceHPOHP:0002360
- Occasional (5% to 29% of cases)
Smooth philtrumHPOHP:0000319
- Occasional (5% to 29% of cases)
SpasticityHPOHP:0001257
- 1 of 4 reported patients
- Occasional (5% to 29% of cases)
Thin ear helixHPOHP:0009905
- Occasional (5% to 29% of cases)
Unilateral renal agenesisHPOHP:0000122
- Occasional (5% to 29% of cases)
Upslanted palpebral fissureHPOHP:0000582
- Occasional (5% to 29% of cases)
Wide nasal bridgeHPOHP:0000431
- Occasional (5% to 29% of cases)
Flexion contractureHPOHP:0001371
- 2 of 6 reported patients
Dysplastic corpus callosumHPOHP:0006989
- 1 of 6 reported patients · Congenital onset
Situs inversus totalisHPOHP:0001696
- 0 of 2 reported patients
Delayed speech and language developmentHPOHP:0000750
Moderate intellectual disabilityHPOHP:0002342