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Disease Profile

Laron 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.

1-9 / 1 000 000

US Estimated

Europe Estimated

Age of onset

Infancy

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ICD-10

E34.3

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)

Growth hormone insensitivity syndrome; Pituitary dwarfism II; Growth hormone receptor deficiency;

Categories

Congenital and Genetic Diseases; Endocrine Diseases

Summary

Laron syndrome is a condition that occurs when the body is unable to utilize growth hormone. It is primarily characterized by short stature. Other signs and symptoms vary but may include reduced muscle strength and endurance; hypoglycemia in infancy; delayed puberty; short limbs (arms and legs); and obesity. It is often caused by changes (mutations) in the GHR gene and is inherited in an autosomal recessive manner. Treatment is focused on improving growth and generally includes injections of insulin-like growth factor 1 (IGF-1).[1][2][3]

Symptoms

Laron syndrome is a rare condition in which the body is unable to use growth hormone. The primary symptom is short stature. Although affected people are generally close to average size at birth, they experience slow growth from early childhood. If left untreated, adult males with Laron syndrome typically reach a maximum height of about 4.5 feet and adult females may be just over 4 feet tall.[1][3]

Other signs and symptoms associated with the condition vary but may include:[1][2][3]

  • Reduced muscle strength and endurance
  • Hypoglycemia in infancy
  • Delayed puberty
  • Small genitals
  • Thin, fragile hair
  • Dental abnormalities
  • Short limbs (arms and legs)
  • Obesity
  • Distinctive facial features (protruding forehead, a sunken bridge of the nose, and blue sclerae)

People affected by Laron syndrome appear to have a reduced risk of cancer and type 2 diabetes.[1][2]

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
Abnormal facial shape
Unusual facial appearance
0001999
Aplasia/Hypoplasia involving the nose
Decreased nasal size
Decreased size of nose

[ more ]

0009924
Delayed eruption of teeth
Delayed eruption
Delayed teeth eruption
Delayed tooth eruption
Eruption, delayed
Late eruption of teeth
Late tooth eruption

[ more ]

0000684
Delayed skeletal maturation
Delayed bone maturation
Delayed skeletal development

[ more ]

0002750
High forehead
0000348
Hypoplastic nasal bridge
Decreased size of nasal bridge
Small bridge of nose
Small nasal bridge

[ more ]

0005281
Microdontia
Decreased width of tooth
0000691
Micrognathia
Little lower jaw
Small jaw
Small lower jaw

[ more ]

0000347
Reduced number of teeth
Decreased tooth count
0009804
Severe short stature
Dwarfism
Proportionate dwarfism
Short stature, severe

[ more ]

0003510
Truncal obesity
0001956
30%-79% of people have these symptoms
Abnormality of the elbow
Abnormality of the elbows
0009811
Brachydactyly
Short fingers or toes
0001156
Delayed puberty
Delayed pubertal development
Delayed pubertal growth
Pubertal delay

[ more ]

0000823
Hypoglycemia
Low blood sugar
0001943
Hypoplasia of penis
Underdeveloped penis
0008736
Motor delay
0001270
Short toe
Short toes
Stubby toes

[ more ]

0001831
Underdeveloped supraorbital ridges
Flattened bony protrusion above eyes
0009891
5%-29% of people have these symptoms
Blue sclerae
Whites of eyes are a bluish-gray color
0000592
Depressed nasal ridge
Flat nose
Recessed nasal ridge

[ more ]

0000457
High pitched voice
0001620
Hypercholesterolemia
Elevated serum cholesterol
Elevated total cholesterol
Increased total cholesterol

[ more ]

0003124
Hypohidrosis
Decreased ability to sweat
Decreased sweating
Sweating, decreased

[ more ]

0000966
Intellectual disability
Mental deficiency
Mental retardation
Mental retardation, nonspecific
Mental-retardation

[ more ]

0001249
Osteoarthritis
Degenerative joint disease
0002758
Prematurely aged appearance
Precociously senile appearance
0007495
Percent of people who have these symptoms is not available through HPO
Abnormal joint morphology
Abnormal shape of joints
Abnormality of the joints
Anomaly of the joints

[ more ]

0001367
Abnormality of metabolism/homeostasis
Laboratory abnormality
Metabolism abnormality

[ more ]

0001939
Autosomal recessive inheritance
0000007
Delayed menarche
Delayed start of first period
0012569
Limb undergrowth
limb shortening
Short limb
Short limbs

[ more ]

0009826
Short long bone
Long bone shortening
0003026
Small face
Short and narrow face
Small facies

[ more ]

0000274

Cause

Laron syndrome is caused by changes (mutations) in the GHR gene. This gene encodes growth hormone receptor, which is a protein found on the outer membrane of cells throughout the body. Growth hormone receptor is designed to recognize and bind growth hormone, which triggers cellular growth and division. When growth hormone is bound to the growth hormone receptors on liver cells, specifically, insulin-like growth factor I (another important growth-promoting hormone) is produced. Mutations in GHR impair the function of growth hormone receptors which interferes with their ability to bind growth hormone. This disrupts normal growth and development of cells and prevents the production of insulin-like growth factor I which causes the many signs and symptoms of Laron syndrome.[1]

Diagnosis

A diagnosis of Laron syndrome is often suspected based on the presence of characteristic signs and symptoms. Additional testing can then be ordered to confirm the diagnosis and rule out other conditions that cause similar features. This generally includes blood tests to measure the levels of certain hormones that are often abnormal in people with Laron syndrome. For example, affected people may have elevated levels of growth hormone and reduced levels of insulin-like growth factor I. Genetic testing for changes (mutations) in the GHR gene can also be used to confirm a diagnosis in some cases.[3][2]

Testing Resources

  • The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.

    Treatment

    There is currently no cure for Laron syndrome. Treatment is primarily focused on improving growth.[4] The only specific treatment available for this condition is subcutaneous injections of insulin-like growth factor 1 (a growth-promoting hormone), often called IGF-1. IGF-1 stimulates linear growth (height) and also improves brain growth and metabolic abnormalities caused by long-term IGF-1 deficiency. It has also been shown to raise blood glucose levels, reduce cholesterol, and increase muscle growth.[3] IGF-1 and GH levels should be closely monitored in people undergoing this treatment because overdosage of IGF-I causes a variety of health problems.[5]

    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.

    • Mecasermin(Brand name: Increlex®) Manufactured by Tercica, Inc.
      FDA-approved indication: Long-term treatment of growth failure in children with severe primary IGF-1 deficiency (Primary IGFD) or with growth hormone (GH) gene deletion who have developed neutralizing antibodies to growth hormone.
      National Library of Medicine Drug Information Portal
    • Mecasermin rinfabate(Brand name: Iplex®) Manufactured by Insmed, Inc.
      FDA-approved indication: Treatment of growth failure in children with severe primary IGF-1 deficiency (Primary IGFD) or with growth hormone (GH) gene deletion who have developed neutralizing antibodies to growth hormone
      National Library of Medicine Drug Information Portal

    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

      Organizations Providing General Support

        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 Laron syndrome. This website is maintained by the National Library of Medicine.
        • 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

          • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
          • 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 Laron syndrome. Click on the link to view a sample search on this topic.

            References

            1. Laron syndrome. Genetics Home Reference. April 2015; https://ghr.nlm.nih.gov/condition/laron-syndrome.
            2. Alan D Rogol, MD, PhD. Growth hormone insensitivity syndromes. UpToDate. August 2015; Accessed 9/29/2015.
            3. Laron Z. Growth hormone insensitivity (Laron syndrome). Rev Endocr Metab Disord. December 2002; 3(4):347-355.
            4. J. Léger. Laron syndrome. Orphanet. November 2009; https://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=EN&Expert=633. Accessed 11/2/2011.
            5. Laron Z. Insulin-like growth factor-I treatment of children with Laron syndrome (primary growth hormone insensitivity). Pediatr Endocrinol Rev. March 2008; 5(3):766-771.

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