Skip to
  1. Homepage
  2. Rare diseases
  3. Search
Simple search

Simple search

(*) mandatory field


Other search option(s)

Microcephalic osteodysplastic primordial dwarfism types I and III

Synonym(s) MOPD types I and III
Microcephalic osteodysplastic primordial dwarfism, Taybi-Linder type
Primordial microcephalic dwarfism, Crachami type
Taybi-Linder syndrome
Prevalence <1 / 1 000 000
Inheritance Autosomal recessive
Age of onset Infancy
  • Q87.1
MeSH -
MedDRA -


Disease definition

Microcephalic osteodysplastic primordial dwarfism (MOPD) types 1 and 3 are characterized by intrauterine and postnatal growth retardation, microcephaly, facial dysmorphism, skeletal dysplasia, low-birth weight and brain anomalies. Although MOPD types 1 and 3 were originally described as two separate entities on the basis of radiological criteria (notably small differences in pelvic and long bone structure), later reports confirmed that the two forms represent different modes of expression of the same syndrome.


The prevalence is unknown but less than 30 cases have been described in the literature so far.

Clinical description

The facial dysmorphism is characterized by a prominent nose with a flat nasal bridge, protruding eyes, a sloping forehead, and micrognathia. Sparse hair and eyebrows, dry skin, short limbs and dislocation of the hips and elbows are other common features. The most frequent neurological manifestations are seizures and intellectual deficit, and reported brain anomalies include lissencephaly, hypoplastic frontal lobes, and agenesis of the corpus callosum or cerebellar vermis.


Although the causative gene remains unknown, homozygosity mapping has allowed identification of a candidate gene region on chromosome 2q (2q14.2-q14.3). Histological studies suggest that MOPD types 1 and 3 result from a basic defect in cell proliferation and tissue differentiation.

Diagnostic methods

Diagnosis is made on the basis of the clinical and radiological phenotype, with common radiological features including short tubular bones, enlarged metaphyses, vertebral and pelvic anomalies, elongated clavicles, bowing of the long bones and cleft vertebral arches.

Differential diagnosis

The differential diagnosis should include MOPD type 2 (see this term) and other syndromes associated with primordial dwarfism (such as Seckel syndrome; see this term).

Antenatal diagnosis

Prenatal diagnosis, by ultrasonography at around 20 weeks of gestation, has been reported in affected families.

Genetic counseling

MOPD types 1 and 3 are transmitted as autosomal recessive traits.

Management and treatment

Treatment issupportive only.


The prognosis is poor with most of the reported patients dying within the first year of life.

Expert reviewer(s)

  • Dr Martine LE MERRER

(*) Required fields.

Attention: Only comments seeking to improve the quality and accuracy of information on the Orphanet website are accepted. For all other comments, please send your remarks via contact us. Only comments written in English can be processed.

Captcha image
The documents contained in this web site are presented for information purposes only. The material is in no way intended to replace professional medical care by a qualified specialist and should not be used as a basis for diagnosis or treatment.