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Disease Profile

Langer mesomelic dysplasia

Prevalence
Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.
<1 / 1 000 000

< 331

US Estimated

< 514

Europe Estimated

Age of onset

Antenatal

ICD-10

Q87.1

Inheritance

Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease

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Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype

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X-linked
dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.

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X-linked
recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder

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Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.

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Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.

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Not applicable

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Other names (AKA)

Dyschondrosteosis, homozygous; Mesomelic dwarfism of the hypoplastic ulna, fibula and mandible type

Categories

Congenital and Genetic Diseases; Musculoskeletal Diseases

Summary

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs.
orphanet

Orpha Number: 2632

Definition
A rare, genetic skeletal dysplasia characterized by severe disproportionate short stature with mesomelic and rhizomelic shortening of the upper and lower limbs.

Epidemiology
The exact prevalence is unknown. More than 100 cases have been described in the literature to date, with most of the patients being reported from populations with a high level of consanguinity.

Clinical description
Langer mesomelic dysplasia (LMD) is a more severe form of Léri-Weill dyschondrosteosis (LWD) and presents at birth with a severely shortened long bones of the limbs (involving both the middle and proximal segments), deformity of the humeral head, angulation of the radial shaft, carpal distortion, a short femoral neck, and absence or hypoplasia of the proximal half of the fibula. Mild hypoplasia of the mandible has been reported in some cases. In contrast to LWD, Madelung deformity is not typically present in LMD. Associated malformations are rare and intellect is normal in almost all reported LMD cases.

Etiology
LMD is inherited in a pseudoautosomal recessive manner and is associated with homozygous or compound heterozygous mutations and deletions of the Short stature HomeobOX (SHOX) gene (which maps to the pseudoautosomal region 1 (PAR1) of the sex chromosomes; Xp22.33 and Yp11.32) or of the upstream or downstream PAR1 (where SHOX enhancer elements are located). LMD is part of a spectrum of disorders (ranging from the most severe, LMD, to LWD, isolated Madelung deformity and so-called idiopathic short stature), all associated with SHOX/PAR1 anomalies. The prevalence of SHOX/PAR1 mutations is estimated at 1/1000.

Diagnostic methods
Diagnosis of LMD may be suspected on the basis of the clinical and radiologic findings and can be confirmed by molecular analysis (preferably multiplex ligation-dependent probe amplification for PAR1 deletions and DNA sequencing for point mutations, small deletions and insertions of SHOX).

Differential diagnosis
During the antenatal period differential diagnosis includes femur-fibula-ulna complex and the Reinhardt-Pfeiffer mesomelic dysplasia.

Antenatal diagnosis
LMD may be suspected by ultrasound at 20 weeks of gestation. Prenatal genetic testing is available; however, requests for testing for these disorders are uncommon but are more frequent for LMD.

Genetic counseling
Genetic counseling should be proposed and families should be informed that SHOX/PAR1 anomalies are inherited in a pseudoautosomal dominant manner. Each child of an individual with LWD has a 50% chance of inheriting the mutation. If both parents have LWD, the offspring have a 50% chance of having LWD, a 25% chance of having LMD, and a 25% chance of having neither condition. All children of an individual with LMD and an unaffected parent will present with LWD.

Management and treatment
There is no effective treatment for LMD. The symptomatic medical management of children with LMD begins at birth and continues into adulthood. Careful monitoring of height, weight, and head circumference is essential.

Prognosis
The short stature and limb deformities are severe but life expectancy is normal.

Visit the Orphanet disease page for more resources.

Symptoms

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.

Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
Abnormality of epiphysis morphology
Abnormal shape of end part of bone
0005930
Abnormality of the carpal bones
0001191
Abnormality of the ulna
0002997
Aplasia/Hypoplasia of the fibula
Absent/small calf bone
Absent/underdeveloped calf bone

[ more ]

0006492
Bowing of the long bones
Bowed long bones
Bowing of long bones

[ more ]

0006487
High palate
Elevated palate
Increased palatal height

[ more ]

0000218
Madelung deformity
0003067
Mesomelic/rhizomelic limb shortening
0005026
Micromelia
Smaller or shorter than typical limbs
0002983
Severe short stature
Dwarfism
Proportionate dwarfism
Short stature, severe

[ more ]

0003510
Short femoral neck
Short neck of thighbone
0100864
Ulnar deviation of finger
Finger bends toward pinky
0009465
Percent of people who have these symptoms is not available through HPO
Autosomal recessive inheritance
0000007
Broad ulna
0003993
Hypoplasia of the radius
Underdeveloped outer large forearm bone
0002984
Hypoplasia of the ulna
Underdeveloped inner large forearm bone
0003022
Lumbar hyperlordosis
Excessive inward curvature of lower spine
0002938
Mesomelia
Disproportionately short middle portion of limb
0003027
Mesomelic short stature
0008845
Micrognathia
Little lower jaw
Small jaw
Small lower jaw

[ more ]

0000347
Radial bowing
Bowing of outer large bone of the forearm
0002986
Rudimentary fibula
Small to absent calf bone
0006381
Short tibia
Short shinbone
Short skankbone

[ more ]

0005736

Treatment

FDA-Approved Treatments

The medication(s) listed below have been approved by the Food and Drug Administration (FDA) as orphan products for treatment of this condition. Learn more orphan products.

  • Somatropin (r-DNA) for injection(Brand name: Humatrope) Manufactured by Eli Lilly and Company
    FDA-approved indication: For the treatment of short stature associated with Turner syndrome in patients whose epiphyses are not closed. In addition, for the treatment of short stature or growth failure in children with cuases of SHOX (short stature homeobox-containing gene) deficiency whose epiphyses are not closed.
    National Library of Medicine Drug Information Portal

Learn more

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.

Where to Start

  • Genetics Home Reference (GHR) contains information on Langer mesomelic dysplasia. This website is maintained by the National Library of Medicine.

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 Langer mesomelic dysplasia. Click on the link to view a sample search on this topic.