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

Book syndrome


Other Names:
Premolar aplasia, hyperhidrosis, and canities prematura; PHC syndrome
Categories:
This disease is grouped under:
Book syndrome is a very rare type of ectodermal dysplasia. Signs and symptoms include premolar aplasia (when the premolars fail to develop); excessive sweating (hyperhidrosis); and premature graying of the hair. Other features that have been reported in only one person include a narrow palate (roof of the mouth); hypoplastic (underdeveloped) nails; eyebrow anomalies; a unilateral simian crease; and poorly formed dermatoglyphics (skin patterns on the hands and feet). Book syndrome is inherited in an autosomal dominant manner.[1]
Last updated: 7/14/2014
To our knowledge, Book syndrome has only been reported in one, large Swedish family (25 cases in 4 generations) and in one other isolated case.[1]

The signs and symptoms reported in the Swedish family included premolar aplasia (when the premolars fail to develop); excessive sweating (hyperhidrosis); and early whitening of the hair. Early whitening of the hair was the most constant symptom, being found in every affected family member. The age of onset of this symptom ranged from age 6 to age 23. In some cases, there was whitening of hair on other parts of the body such as the armipits, genital hair, and eyebrows. Two-thirds of the affected people had an abnormality of the sweat glands.[2]

In the isolated case, additional features that were reported include a narrow palate (roof of the mouth); hypoplastic (underdeveloped) nails; eyebrow anomalies; a unilateral simian crease; and poorly formed dermatoglyphics (skin patterns on the hands and feet).[1]
Last updated: 7/14/2014

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.

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Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
Hyperhidrosis
Excessive sweating
Increased sweating
Profuse sweating
Sweating
Sweating profusely
Sweating, increased
[ more ] 		0000975
Hypodontia
Failure of development of between one and six teeth
0000668
Premature graying of hair
Early graying
Premature graying
Premature greying
Premature hair graying
[ more ] 		0002216
Small hand
Disproportionately small hands
0200055
30%-79% of people have these symptoms
Abnormal eyebrow morphology
Abnormality of the eyebrow
0000534
Bilateral single transverse palmar creases 0007598
Hypoplastic fingernail
Small fingernail
Underdeveloped fingernail
[ more ] 		0001804
Narrow palate
Narrow roof of mouth
0000189
Percent of people who have these symptoms is not available through HPO
Autosomal dominant inheritance 0000006
Palmoplantar hyperhidrosis
Excessive sweating of palms and soles
0007410
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Last updated: 7/1/2020
To our knowledge, Book syndrome has only been reported in one, large Swedish family (25 cases in 4 generations) and in one other isolated case.[1] In the Swedish family, the syndrome was inherited in an autosomal dominant manner.[1][2] In autosomal dominant inheritance, having a mutation in only one copy of the responsible gene is enough to cause signs and symptoms of the condition. When a person with an autosomal dominant condition has children, each child has a 50% (1 in 2) risk to inherit the mutated copy of the gene.
Last updated: 7/14/2014
Due to the rarity of Book syndrome and scarcity of reports in the medical literature, we are unaware of specific information about diagnosing Book syndrome.

In general, ectodermal dysplasias are diagnosed by the presence of specific symptoms affecting the hair, nails, sweat glands, and/or teeth. When a person has at least two types of abnormal ectodermal features (e.g., malformed teeth and extremely sparse hair), the person is typically identified as being affected by an ectodermal dysplasia. Specific genetics tests to diagnose ectodermal dysplasia are available for only a limited number of ectodermal dysplasias.[3] Unfortunately, there currently is no genetic test for Book syndrome because the gene responsible for the condition has not yet been identified.

People who are interested in learning more about a diagnosis of ectodermal dysplasia for themselves or family members should speak with their dermatologist and/or dentist. These specialists can help determine whether a person has signs and/or symptoms of ectodermal dysplasia.
Last updated: 7/14/2014

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

  • The Centers for Mendelian Genomics program is working to discover the causes of rare genetic disorders. For more information about applying to the research study, please visit their website.

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.

Where to Start

  • DermNet NZ is an online resource about skin diseases developed by the New Zealand Dermatological Society Incorporated. DermNet NZ provides information about this condition.
  • 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 Book syndrome. 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

  • My father is 63 years old and as been living with PHC for over 25 years. I can't find much information about this disease and I am concerned about the health of myself and my children. I specifically would like to know the early signs and symptoms as well as testing procedures. See answer


  1. Book syndrome. Orphanet. October, 2013; http://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=en&Expert=1262. Accessed 7/10/2014.
  2. J. A. Book. Clinical and genetical studies of hypodontia. I. Premolar aplasia, hyperhidrosis, and canities prematura; A new hereditary syndrome in man. Am J Hum Genet. September, 1950; 2(3):240-263. Accessed 7/14/2014.
  3. About Ectodermal Dysplasias. National Foundation for Ectodermal Dysplasias. 2010; http://nfed.org/index.php/about_ed/about-ectodermal-dysplasias. Accessed 7/14/2014.