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

Kallmann syndrome 1



Other Names:
KAL1; Kallmann syndrome, X-linked; Kallmann syndrome, type 1, X-linked
Categories:
This disease is grouped under:

Kallmann syndrome 1 is an inherited disorder characterized by delayed or absent puberty and an impaired sense of smell. Other symptoms may include color blindness, cleft lip or palate, abnormal eye movements, hearing loss, failure of one of the kidneys to develop, mirror image hand movements, abnormalities of tooth development, and infertility. This disorder is a form of hypogonadotropic hypogonadism. Affected males are usually born with a small penis and undescended testicles. Affected females usually do not begin menstruating at puberty and have little or no breast development.[1][2] Kallmann syndrome 1 is the most common type of Kallmann syndrome (there are four types identified at this time). It is caused by mutations in the KAL1 gene and is inherited in an X-linked recessive fashion.[1]  
Last updated: 12/22/2011

The features of Kallmann syndrome 1 vary, even among affected people in the same family. The condition is characterized by delayed or absent puberty and an impaired sense of smell. It is a form of hypogonadotropic hypogonadism, which is a condition affecting the production of hormones that direct sexual development. Males with hypogonadotropic hypogonadism are often born with an unusually small penis and undescended testes. At puberty, most affected individuals do not develop secondary sex characteristics, such as the growth of facial hair and deepening of the voice in males. Affected females usually do not begin menstruating at puberty and have little or no breast development. In some people, puberty is incomplete or delayed.[1]

In Kallmann syndrome 1, the sense of smell is either diminished or completely absent. This feature distinguishes Kallmann syndrome from most other forms of hypogonadotropic hypogonadism, which do not affect the sense of smell. Many people with Kallmann syndrome are not aware that they are unable to detect odors until the impairment is discovered through testing.[1]

Additional signs and symptoms can include a failure of one kidney to develop, a cleft lip or palate, abnormal eye movements, hearing loss, and abnormalities of tooth development. Some affected individuals have a condition called bimanual synkinesis, in which the movements of one hand are mirrored by the other hand.[1]

Last updated: 12/22/2011

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 54 |
Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
Anosmia
Lost smell
0000458
Anterior hypopituitarism 0000830
Decreased fertility
Abnormal fertility
0000144
Decreased testicular size
Small testes
Small testis
[ more ]
0008734
Delayed puberty
Delayed pubertal development
Delayed pubertal growth
Pubertal delay
[ more ]
0000823
Erectile dysfunction
Abnormal erection
Erectile abnormalities
[ more ]
0100639
Hypogonadotropic hypogonadism 0000044
Hyposmia 0004409
Hypothalamic gonadotropin-releasing hormone deficiency 0003164
Micropenis
Short penis
Small penis
[ more ]
0000054
30%-79% of people have these symptoms
Abnormality of the voice
Voice abnormality
0001608
Breast hypoplasia
Underdeveloped breasts
0003187
Cryptorchidism
Undescended testes
Undescended testis
[ more ]
0000028
Reduced bone mineral density
Low solidness and mass of the bones
0004349
5%-29% of people have these symptoms
Abnormal morphology of female internal genitalia 0000008
Abnormality of cardiovascular system morphology 0030680
Ataxia 0001251
Bimanual synkinesia
Hand mirror movements
Mirror hand movements
Mirror movements
[ more ]
0001335
Cleft palate
Cleft roof of mouth
0000175
Color vision defect
Abnormal color vision
Abnormality of color vision
[ more ]
0000551
Delayed skeletal maturation
Delayed bone maturation
Delayed skeletal development
[ more ]
0002750
Dysarthria
Difficulty articulating speech
0001260
Dyspareunia 0030016
Facial asymmetry
Asymmetry of face
Crooked face
Unsymmetrical face
[ more ]
0000324
Gait disturbance
Abnormal gait
Abnormal walk
Impaired gait
[ more ]
0001288
Gynecomastia
Enlarged male breast
0000771
Ichthyosis 0008064
Muscle weakness
Muscular weakness
0001324
Muscular hypotonia
Low or weak muscle tone
0001252
Nystagmus
Involuntary, rapid, rhythmic eye movements
0000639
Obesity
Having too much body fat
0001513
Paraplegia
Leg paralysis
0010550
Pes cavus
High-arched foot
0001761
Pes planus
Flat feet
Flat foot
[ more ]
0001763
Primary amenorrhea 0000786
Ptosis
Drooping upper eyelid
0000508
Recurrent fractures
Increased fracture rate
Increased fractures
Multiple fractures
Multiple spontaneous fractures
Varying degree of multiple fractures
[ more ]
0002757
Reduced number of teeth
Decreased tooth count
0009804
Renal agenesis
Absent kidney
Missing kidney
[ more ]
0000104
Seizure 0001250
Sensorineural hearing impairment 0000407
Skeletal dysplasia 0002652
Tremor 0001337
Visual impairment
Impaired vision
Loss of eyesight
Poor vision
[ more ]
0000505
Percent of people who have these symptoms is not available through HPO
Azoospermia
Absent sperm in semen
0000027
Eunuchoid habitus 0003782
High palate
Elevated palate
Increased palatal height
[ more ]
0000218
Leydig cell insensitivity to gonadotropin 0002929
Olfactory lobe agenesis
Olfactory lobe absence
0001341
Sparse pubic hair
Decreased sexual hair
0002225
Testicular atrophy
Testicular degeneration
0000029
Unilateral renal agenesis
Absent kidney on one side
Missing one kidney
Single kidney
[ more ]
0000122
X-linked inheritance 0001417
X-linked recessive inheritance 0001419
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Last updated: 7/1/2020

Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.

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.

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


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

  • ClinicalTrials.gov lists trials that are related to Kallmann syndrome 1. Click on the link to go to ClinicalTrials.gov to read descriptions of these studies.

    Please note: Studies listed on the ClinicalTrials.gov website are listed for informational purposes only; being listed does not reflect an endorsement by GARD or the NIH. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.

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

Social Networking Websites


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 Kallmann syndrome 1. 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

  • GeneReviews provides current, expert-authored, peer-reviewed, full-text articles describing the application of genetic testing to the diagnosis, management, and genetic counseling of patients with specific inherited conditions.
  • 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 Kallmann syndrome 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.


  1. Kallmann syndrome. Genetics Home Reference. 2008; http://ghr.nlm.nih.gov/condition/kallmann-syndrome. Accessed 12/22/2011.
  2. Pallais JC, Au M, Pitteloud N, Seminara S, Crowley WE. Kallmann syndrome. GeneReviews. 2011; http://www.ncbi.nlm.nih.gov/books/NBK1334/. Accessed 12/22/2011.