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Other Names for this Disease
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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). 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 a single gene, chromosome abnormalities, or substances that cause birth defects (teratogens).
- Nonsyndromic holoprosencephaly. Genetics Home Reference. http://ghr.nlm.nih.gov/condition/nonsyndromic-holoprosencephaly. Accessed September 30, 2010.
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- Genetics Home Reference (GHR) contains information on Holoprosencephaly. Click on the link to go to GHR and review the information.
- Medscape Reference provides information on this topic. Click on the link to view this information. You may need to register to view the medical textbook, but registration is free.
- 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.
- Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge. Click on the link to read information on this topic.
- 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.
- The The Online Mendelian Inheritance in Man (OMIM) database contains genetics resources that discuss Holoprosencephaly. Click on the link to go to OMIM and review these resources.