Holoprosencephaly (HPE, once known as arhinencephaly) is a cephalic disorder in which the prosencephalon (the forebrain of the embryo) fails to develop into two hemispheres. Normally, the forebrain is formed and the face begins to develop in the fifth and sixth weeks of human pregnancy. Hox genes, which guide placement of embryonic structures, fail to activate along the midline of the head, allowing structures that are normally paired on the left and right to merge. The condition also occurs in other species, as with Cy, the Cyclops kitten.
The condition can be mild or severe. According to the National Institute of Neurological Disorders and Stroke (NINDS), "in most cases of holoprosencephaly, the malformations are so severe that babies die before birth.
When the embryo's forebrain does not divide to form bilateral cerebral hemispheres (the left and right halves of the brain), it causes defects in the development of the face and in brain structure and function.
In less severe cases, babies are born with normal or near-normal brain development and facial deformities that may affect the eyes, nose, and upper lip.
This text uses material from Wikipedia licensed under CC BY-SA
Latest Spotlight News
Inside each of us is our own internal timing device. It drives everything from sleep cycles to metabolism, but the inner-workings of this so-called "circadian clock" are complex, and the molecular processes behind it have ...
Study shows cultural images may hinder proficiency in second language skills
(Medical Xpress)—A team of combined researchers from Columbia Business School and Singapore Management University has found that people who have learned a second language become less proficient at speaking ...
The discerning fruit fly: Linking brain-cell activity and behavior in smell recognition
Behind the common expression "you can't compare apples to oranges" lies a fundamental question of neuroscience: How does the brain recognize that apples and oranges are different? A group of neuroscientists ...
Recent research has shown that cancer cells have a much different – and more complex – metabolism than normal cells. Now, scientists at The University of Texas at Dallas have found that exploiting these differences might ...
Researchers have discovered and mapped the signaling network between two previously unconnected proteins, exposing a link that, if broken, could cut off cancer cell growth at its starting point.
Men who lose sleep during the work week may be able to lower their risk of developing Type 2 diabetes by getting more hours of sleep, according to Los Angeles Biomedical Research Institute (LA BioMed) research findings presented ...
Aspirin is known to lower risk for some cancers, and a new study led by a UC San Francisco scientist points to a possible explanation, with the discovery that aspirin slows the accumulation of DNA mutations in abnormal cells ...
Balancing act: Mitochondrial protein coordinates a little-known enzyme that controls how fat is stored or burned
(Medical Xpress)—Calories in, calories out. Any dieter is familiar with the two sides of the equation for weight loss, usually reduced to eating less and exercising more. But what controls the body's balance ...
The rhythm of everything
Dawn triggers basic biological changes in the waking human body. As the sun rises, so does heart rate, blood pressure and body temperature. The liver, the kidneys and many natural processes also begin shifting ...
The link between genes and cancer
(Medical Xpress)—When people think about genes and their relationship to cancer, most probably think about a person's hereditary cancer risk, especially after Angelina Jolie's recent news about her inherited ...
