National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Microcephalic osteodysplastic primordial dwarfism type 1


Other Names:
MOPD 1; Microcephalic osteodysplastic primordial dwarfism types 1 and 3; Osteodysplastic primordial dwarfism type I; MOPD 1; Microcephalic osteodysplastic primordial dwarfism types 1 and 3; Osteodysplastic primordial dwarfism type I; Brachymelic primordial dwarfism; Taybi-Linder syndrome; Primordial microcephalic dwarfism, Crachami type; Cephaloskeletal dysplasia; Low-birth-weight dwarfism with skeletal dysplasia See More
Categories:
Microcephalic osteodysplastic primordial dwarfism type 1 (MOPD1) is a genetic condition that is mainly characterized by intrauterine and post-natal growth retardation; an abnormally small head size (microcephaly); abnormal bone growth (skeletal dysplasia); distinctive facial features; and brain anomalies. Other signs and symptoms include sparse hair and eyebrows; dry skin; short limbs; dislocation of the hips and elbows; seizures; and intellectual disability.[1] It is caused by mutations in the RNU4ATAC gene and is inherited in an autosomal recessive manner.[2] Treatment is supportive only. The prognosis is poor with most affected individuals dying within the first year of life.[1] MOPD types 1 and 3 were originally thought to be separate entities, but more recent reports have confirmed that the two forms are part of the same syndrome.[1]
Last updated: 11/11/2011
Individuals with MOPD1 may have low birth weight, growth retardation, short limbs, broad hands, small head size (microcephaly), abnormal bone growth (skeletal dysplasia) and a distinct facial appearance. Facial characteristics may include a sloping forehead; protruding eyes; prominent nose with a flat nasal bridge; and small jaw (micrognathia).[3][1] In addition, babies with MOPD1 may experience short episodes of stopped breathing (apnea) and seizures.[3] Affected individuals also commonly have sparse hair and eyebrows; dry skin; dislocation of the hips or elbows; and intellectual disability.[1] Brain abnormalities that have been reported include lissencephaly, hypoplastic (underdeveloped) frontal lobes, and agenesis of the corpus callosum or cerebellar vermis (the nerve tissue that connects the two halves of the cerebellum).[1]
Last updated: 11/11/2011

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Showing of 112 |
Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
Abnormal calcium-phosphate regulating hormone level 0100530
Abnormal form of the vertebral bodies 0003312
Abnormality of the intervertebral disk 0005108
Abnormality of the metacarpal bones
Abnormality of the long bone of hand
0001163
Abnormality of the metaphysis
Abnormality of the wide portion of a long bone
0000944
Abnormality of the pubic bone
Abnormality of the pubic bones
Abnormality of the pubis
[ more ] 		0003172
Abnormally ossified vertebrae
Abnormal bone maturation of vertebra
0100569
Alopecia
Hair loss
0001596
Aplasia/hypoplasia of the femur
Absent/small thighbone
Absent/underdeveloped thighbone
[ more ] 		0005613
Aplastic clavicle
Absent collarbone
0006660
Bifid femur
Notched thighbone
Split thighbone
[ more ] 		0010443
Bilateral single transverse palmar creases 0007598
Brachydactyly
Short fingers or toes
0001156
Broad distal phalanx of finger
Broad outermost finger bone
0009836
Bulbous nose 0000414
Delayed skeletal maturation
Delayed bone maturation
Delayed skeletal development
[ more ] 		0002750
Dyspnea
Trouble breathing
0002094
Epileptic spasm 0011097
Generalized non-motor (absence) seizure
Brief seizures with staring spells
0002121
Glaucoma 0000501
Global developmental delay 0001263
Hydronephrosis 0000126
Hydroureter 0000072
Intellectual disability
Mental deficiency
Mental retardation
Mental retardation, nonspecific
Mental-retardation
[ more ] 		0001249
Intrauterine growth retardation
Prenatal growth deficiency
Prenatal growth retardation
[ more ] 		0001511
Large hands
large hand
0001176
Large iliac wings 0008818
Long nose
Elongated nose
Increased height of nose
Increased length of nose
Increased nasal height
Increased nasal length
Nasal elongation
[ more ] 		0003189
Loss of eyelashes
Eyelashes fell out
Missing eyelashes
[ more ] 		0011457
Low-set ears
Low set ears
Lowset ears
[ more ] 		0000369
Microcephaly
Abnormally small skull
Decreased circumference of cranium
Decreased size of skull
Reduced head circumference
Small head circumference
[ more ] 		0000252
Micrognathia
Little lower jaw
Small jaw
Small lower jaw
[ more ] 		0000347
Micromelia
Smaller or shorter than typical limbs
0002983
Muscle stiffness 0003552
Osteomalacia
Softening of the bones
0002749
Osteopenia 0000938
Osteoporosis 0000939
Posteriorly rotated ears
Ears rotated toward back of head
0000358
Premature birth
Premature delivery of affected infants
Preterm delivery
[ more ] 		0001622
Prominent nose
Big nose
Disproportionately large nose
Increased nasal size
Increased size of nose
Large nose
Pronounced nose
[ more ] 		0000448
Prominent occiput
Prominent back of the skull
Prominent posterior skull
[ more ] 		0000269
Proptosis
Bulging eye
Eyeballs bulging out
Prominent eyes
Prominent globes
Protruding eyes
[ more ] 		0000520
Respiratory failure 0002878
Retrognathia
Receding chin
Receding lower jaw
Weak chin
Weak jaw
[ more ] 		0000278
Rickets
Weak and soft bones
0002748
Rigidity
Muscle rigidity
0002063
Severe short stature
Dwarfism
Proportionate dwarfism
Short stature, severe
[ more ] 		0003510
Short neck
Decreased length of neck
0000470
Short palm 0004279
Sparse hair 0008070
Spasticity
Involuntary muscle stiffness, contraction, or spasm
0001257
Specific learning disability 0001328
Status epilepticus
Repeated seizures without recovery between them
0002133
Thin eyebrow
Thin eyebrows
0045074
30%-79% of people have these symptoms
Abnormality of the tragus 0009912
Bifid uvula 0000193
Clinodactyly of the 5th finger
Permanent curving of the pinkie finger
0004209
Cryptorchidism
Undescended testes
Undescended testis
[ more ] 		0000028
Dolichocephaly
Long, narrow head
Tall and narrow skull
[ more ] 		0000268
Downslanted palpebral fissures
Downward slanting of the opening between the eyelids
0000494
Malar flattening
Zygomatic flattening
0000272
Sloping forehead
Inclined forehead
Receding forehead
[ more ] 		0000340
Submucous cleft hard palate 0000176
Thick vermilion border
Full lips
Increased volume of lip
Plump lips
Prominent lips
Thick lips
[ more ] 		0012471
Thickened nuchal skin fold
Thickened skin folds of neck
Thickened skin over the neck
[ more ] 		0000474
Percent of people who have these symptoms is not available through HPO
11 pairs of ribs 0000878
Abnormality of the pinna
Abnormally shaped ears
Auricular malformation
Deformed ears
Malformed ears
[ more ] 		0000377
Absent knee epiphyses
Absent knee end part
0006400
Agenesis of cerebellar vermis 0002335
Agenesis of corpus callosum 0001274
Atrial septal defect
An opening in the wall separating the top two chambers of the heart
Hole in heart wall separating two upper heart chambers
[ more ] 		0001631
Autosomal recessive inheritance 0000007
Bowed humerus
Bowed long bone in upper arm
0003865
Cleft vertebral arch 0004616
Coarctation of aorta
Narrowing of aorta
Narrowing of the aorta
[ more ] 		0001680
Disproportionate short stature 0003498
Dry skin 0000958
Elbow dislocation
Dislocations of the elbows
Elbow dislocations
[ more ] 		0003042
Elbow flexion contracture
Contractures of elbows
Elbow contracture
Elbow contractures
[ more ] 		0002987
Enlarged metaphyses
Enlarged wide portion of a long bone
0003051
Failure to thrive
Faltering weight
Weight faltering
[ more ] 		0001508
Femoral bowing
Bowed thighbone
0002980
Gray matter heterotopia 0002282
Hip contracture 0003273
Hip dislocation
Dislocated hips
Dislocation of hip
[ more ] 		0002827
Hyperkeratosis 0000962
Hypoplasia of the frontal lobes
Underdeveloped frontal lobe
0007333
Hypoplastic ilia 0000946
Knee flexion contracture 0006380
Limb undergrowth
limb shortening
Short limb
Short limbs
[ more ] 		0009826
Long clavicles
Long collarbone
0000890
Long foot
Disproportionately large feet
large feet
long feet
[ more ] 		0001833
Micropenis
Short penis
Small penis
[ more ] 		0000054
Microtia
Small ears
Underdeveloped ears
[ more ] 		0008551
Oligohydramnios
Low levels of amniotic fluid
0001562
Pachygyria
Fewer and broader ridges in brain
0001302
Platyspondyly
Flattened vertebrae
0000926
Prolonged neonatal jaundice
Prolonged yellowing of skin in newborn
0006579
Renal cyst
Kidney cyst
0000107
Renal hypoplasia
Small kidneys
Underdeveloped kidneys
[ more ] 		0000089
Seizure 0001250
Short femur
Short thighbone
0003097
Short humerus
Short long bone of upper arm
Short upper arms
[ more ] 		0005792
Short metacarpal
Shortened long bone of hand
0010049
Shoulder flexion contracture 0003044
Single transverse palmar crease 0000954
Small anterior fontanelle 0000237
Sparse and thin eyebrow
Thin, sparse eyebrows
0000535
Sparse eyelashes
Scant eyelashes
Scanty eyelashes
Thin eyelashes
[ more ] 		0000653
Sparse scalp hair
Reduced/lack of hair on scalp
Scalp hair, thinning
Sparse, thin scalp hair
sparse-absent scalp hair
[ more ] 		0002209
Stillbirth
Stillborn
0003826
Tetralogy of Fallot 0001636
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Last updated: 7/1/2020
Microcephalic osteodysplastic primordial dwarfism type 1 (MOPD1) has been shown to be caused by mutations in the RNU4ATAC gene.[2]
Last updated: 11/11/2011
MOPD1 is thought to be inherited in an autosomal recessive manner.[3] This means that affected individuals have abnormal gene changes (mutations) in both copies of the disease-causing gene, with one copy inherited from each parent. The parents who each carry one abnormal copy of the gene are referred to as carriers; carriers typically do not show signs or symptoms of an autosomal recessive condition. When two carriers have children, each child has a 25% (1 in 4) risk to have the condition, a 50% (1 in 2) risk to be a carrier like each of the parents, and a 25% chance to not have the condition and not be a carrier.
Last updated: 11/11/2011
At this time there are no specific treatments for MOPD1. Treatment is generally supportive. The prognosis is poor for affected individuals, with most of the reported patients dying within the first year of life.[1]
Last updated: 11/11/2011
Prognosis can vary from patient to patient, however it is generally poor. Some babies are stillborn. Most infants pass away with in a year, often due to infectious diseases.[3]
Last updated: 9/26/2013

If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments.

If you can’t find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care.

You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists.

Healthcare Resources

Related diseases are conditions that have similar signs and symptoms. A health care provider may consider these conditions in the table below when making a diagnosis. Please note that the table may not include all the possible conditions related to this disease.

Conditions with similar signs and symptoms from Orphanet
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).
Visit the Orphanet disease page for more information.

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

  • The U.S. National Institutes of Health, through the National Library of Medicine, developed ClinicalTrials.gov to provide patients, family members, and members of the public with current information on clinical research studies. There is a study titled Pediatric Patients With Metabolic or Other Genetic Disorders which may be of interest to you.
  • The U.S. National Institutes of Health, through the National Library of Medicine, developed ClinicalTrials.gov to provide patients, family members, and members of the public with current information on clinical research studies. There is a study titled Evaluation and Treatment of Skeletal Diseases which may be of interest to you.

Patient Registry

  • A registry supports research by collecting of information about patients that share something in common, such as being diagnosed with Microcephalic osteodysplastic primordial dwarfism type 1. The type of data collected can vary from registry to registry and is based on the goals and purpose of that registry. Some registries collect contact information while others collect more detailed medical information. Learn more about registries.

    Registries for Microcephalic osteodysplastic primordial dwarfism type 1:
    International Skeletal Dysplasia Registry (ISDR)
     

Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

In-Depth Information

  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Microcephalic osteodysplastic primordial dwarfism type 1. Click on the link to view a sample search on this topic.

Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know. Submit a new question

  • Does the "M" in MOPD stand for microcephaly or Majewski? What is the difference between the types of MOPD in terms of genetics? See answer

  • Do you have information on MOPD Type I that I could share with a family I know? See answer


  1. Microcephalic osteodysplastic primordial dwarfism types 1 and 3. Orphanet. November 2008; http://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=EN&Expert=2636. Accessed 11/11/2011.
  2. Ada Hamosh. MICROCEPHALIC OSTEODYSPLASTIC PRIMORDIAL DWARFISM, TYPE I; MOPD1. OMIM. April 22, 2011; http://omim.org/entry/210710. Accessed 11/11/2011.
  3. Spranger JW, Brill PW, Poznanski A. Bone Dysplasias: An atlas of genetic disorders of the skeletal development. 2nd ed. Oxford, NY: Oxford University Press; 2002;