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Disease Profile

Hanhart syndrome

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

Neonatal

ICD-10

Q87.2

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.

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)

Aglossia adactylia; Hypoglossia-hypodactylia syndrome; Peromelia with micrognathia

Categories

Congenital and Genetic Diseases; Mouth Diseases; Musculoskeletal Diseases

Summary

Hanhart syndrome is a rare condition that primarily affects the craniofacial region and the limbs (arms and legs). People affected by this condition are often born with a short, incompletely developed tongue; absent or partially missing fingers and/or toes; abnormalities of the arms and/or legs; and an extremely small jaw. The severity of these physical abnormalities varies greatly among affected people, and children with this condition often have some, but not all, of the symptoms. The cause of Hanhart syndrome is not fully understood. Treatment depends on the signs and symptoms present in each person.[1][2][3]

Symptoms

The signs and symptoms of Hanhart syndrome vary, but may include:[3][4][1]

  • Small mouth
  • Short, incompletely developed tongue (hypoglossia)
  • Absent, partially missing, or shortened fingers and/or toes
  • Jaw abnormalities such as micrognathia, retrognathia (receding jaw), or partially missing mandible (lower jaw)
  • High-arched, narrow, or cleft palate
  • Absent or unusually formed arms and/or legs
  • Missing teeth
  • Absence of major salivary glands

Some infants with Hanhart syndrome may be born with paralysis of certain areas of the face. If the tongue and/or mouth are affected, this can worsen feeding difficulties that are already present due to the craniofacial abnormalities listed above.[3]

The severity of the physical abnormalities associated with Hanhart syndrome varies greatly among affected people, and children with this disorder often have some, but not all, of the 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
Aplasia/Hypoplasia of the tongue
0010295
Hypoplasia of the zygomatic bone
Cheekbone underdevelopment
Decreased size of cheekbone
Underdevelopment of cheekbone

[ more ]

0010669
Micrognathia
Little lower jaw
Small jaw
Small lower jaw

[ more ]

0000347
Narrow mouth
Small mouth
0000160
Upper limb phocomelia
0009813
30%-79% of people have these symptoms
Abnormal fingernail morphology
Abnormal fingernails
Abnormality of the fingernails

[ more ]

0001231
Adactyly
0009776
Brachydactyly
Short fingers or toes
0001156
Cleft palate
Cleft roof of mouth
0000175
Finger syndactyly
0006101
Hypodontia
Failure of development of between one and six teeth
0000668
Short distal phalanx of finger
Short outermost finger bone
0009882
Split hand
Claw hand
Claw hand deformities
Claw hands
Claw-hand deformities
Split-hand

[ more ]

0001171
Telecanthus
Corners of eye widely separated
0000506
Wide nasal bridge
Broad nasal bridge
Broad nasal root
Broadened nasal bridge
Increased breadth of bridge of nose
Increased breadth of nasal bridge
Increased width of bridge of nose
Increased width of nasal bridge
Nasal bridge broad
Wide bridge of nose
Widened nasal bridge

[ more ]

0000431
5%-29% of people have these symptoms
Abnormal cranial nerve morphology
0001291
Anal atresia
Absent anus
0002023
Death in infancy
Infantile death
Lethal in infancy

[ more ]

0001522
Facial asymmetry
Asymmetry of face
Crooked face
Unsymmetrical face

[ more ]

0000324
Feeding difficulties in infancy
0008872
Gastroschisis
0001543
High palate
Elevated palate
Increased palatal height

[ more ]

0000218
Intellectual disability
Mental deficiency
Mental retardation
Mental retardation, nonspecific
Mental-retardation

[ more ]

0001249
Jejunal atresia
0005235
Neurological speech impairment
Speech disorder
Speech impairment
Speech impediment

[ more ]

0002167
Percent of people who have these symptoms is not available through HPO
Aglossia
Failure of development of tongue
0012730
Autosomal dominant inheritance
0000006
Epicanthus
Eye folds
Prominent eye folds

[ more ]

0000286
Microglossia
Abnormally small tongue
Underdevelopment of the tongue

[ more ]

0000171
Retrognathia
Receding chin
Receding lower jaw
Weak chin
Weak jaw

[ more ]

0000278
Sporadic
No previous family history
0003745

Cause

The exact underlying cause of Hanhart syndrome is currently unknown. However, researchers suspect that there may be genetic and/or environmental factors that contribute to the development of the condition. To date, no specific disease-causing genes have been identified. Possible environmental factors including:[2][1]

Diagnosis

A diagnosis of Hanhart syndrome is typically made based on the presence of characteristic signs and symptoms. In some cases, the diagnosis may be suspected before birth if concerning features are seen on ultrasound.[3][1]

Treatment

Because Hanhart syndrome affects many different systems of the body, medical management is often provided by a team of doctors and other healthcare professionals. Treatment for this condition varies because it depends on the signs and symptoms present in each person. For example, limb and/or craniofacial abnormalities may be treated with surgery and/or prostheses. Affected children may also need speech therapy, physical therapy, and/or occupational therapy.[3][2][1]

Organizations

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

    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

    • The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.

      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 Hanhart syndrome. Click on the link to view a sample search on this topic.

        References

        1. Manisha Goyal, Ankur Singh, Pratiksha Singh, and Seema Kapoor. Hypoglossia-Hypodactyly Syndrome with Short Stature A Case Report. J Clin Diagn Res. April 2014; 8(4):SD01–SD02. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4064859/.
        2. Hypoglossia-hypodactyly syndrome. Orphanet. July 2005; https://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=EN&Expert=989.
        3. Hanhart Syndrome. NORD. February 2008; https://www.rarediseases.org/rare-disease-information/rare-diseases/byID/1022/viewAbstract.
        4. HYPOGLOSSIA-HYPODACTYLIA. OMIM. September 2012; https://www.omim.org/entry/103300.
        5. Gathwala G, Singh J, Dalal P, Garg A.. Hypoglossia-hypodactyly syndrome in a newborn. J Craniomaxillofac Surg. March 2011; 39(2):99-101. https://www.ncbi.nlm.nih.gov/pubmed/20673638.

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