Other Names for this Disease
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 Many facial defects can be present; in general, the most serious the brain defect is, the most serious the face defect will be. The most severely affected individuals have one central eye (cyclopia) and a tubular nasal structure (proboscis) located above the eye. In the less severe forms, the brain is partially divided and the eyes are usually set close together (hypotelorism). Holoprosencephaly can be caused by mutations in 14 different genes, chromosome abnormalities, or substances or infections that cause birth defects (teratogens). It may also be a feature of several genetic syndromes, each with unique characteristics. Alobar holoprosencephaly is lethal in all cases, but people with milder types can survive for several months depending on the associated problems they might have. Treatment is symptomatic.Holoprosencephaly is an abnormality of brain development that also affects the head and face. Normally, the brain divides into two halves (hemispheres) during early development. Holoprosencephaly occurs when the brain fails to divide properly into the right and left hemispheres. There are four types of holoprosencephaly according to the degree of brain division. From most to least severe, the types are known as alobar, semi-lobar, lobar, and middle interhemispheric variant (MIHV).
Last updated: 2/24/2016
- Solomon BD, Gropman A & Muenke M. Holoprosencephaly Overview. GeneReviews. August 29, 2013; http://www.ncbi.nlm.nih.gov/books/NBK1530/.
- Nonsyndromic holoprosencephaly. Genetics Home Reference. September 2010; http://ghr.nlm.nih.gov/condition/nonsyndromic-holoprosencephaly.
- Genetics Home Reference (GHR) contains information on Holoprosencephaly. This website is maintained by the National Library of Medicine.
- The National Human Genome Research Institute's (NHGRI) mission encompasses a broad range of studies aimed at understanding the structure and function of the human genome and its role in health and disease. Click on the link to view the information page on this topic.
- The National Institute of Neurological Disorders and Stroke (NINDS) collects and disseminates research information related to neurological disorders. Click on the link to view information on this topic.
- The National Organization for Rare Disorders (NORD) is a federation of more than 130 nonprofit voluntary health organizations serving people with rare disorders. Click on the link to view information on this topic.
- Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
- Online Mendelian Inheritance in Man (OMIM) lists the subtypes and associated genes for Holoprosencephaly in a table called Phenotypic Series. Each entry in OMIM includes 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 Holoprosencephaly. Click on the link to view a sample search on this topic.