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Marfan syndrome

Abraham Lincoln
History:
The syndrome is inherited as a dominant trait, carried by the gene FBN1, which encodes the connective protein fibrillin-1. People have a pair ofFBN1 genes. Because it is dominant, people who have inherited one affected FBN1 gene from either parent will have Marfan syndrome. Marfan syndrome has a range of expressions, from mild to severe. The most serious complications are defects of the heart valves and aorta. It may also affect the lungs, the eyes, the dural sac surrounding the spinal cord, the skeleton and the hard palate. In addition to being a connective protein that forms the structural support for tissues outside the cell, the normal fibrillin-1 protein binds to another protein, transforming growth factor beta (TGF-β). TGF-β has deleterious effects on vascular smooth muscle development and the integrity of the extracellular matrix. Researchers now believe, secondary to mutated fibrillin, excessive TGF-β at the lungs, heart valves, and aorta weakens the tissues and causes the features of Marfan syndrome. Since angiotensin II receptor antagonists (ARBs) also reduce TGF-β, ARBs (losartan, etc.) have been tested in a small sample of young, severely affected Marfan syndrome patients. In some patients, the growth of the aorta was indeed reduced. Marfan syndrome is named after Antoine Marfan the French pediatrician who first described the condition in 1896. The gene linked to the disease was first identified by Hal Dietz  and Francesco Ramirez in 1991.

Clinical diagnosis or characteristics:
MFS is a highly variable systemic tissue disorder with clinical characteristics similar to a variety of other hereditary disorders from which it should be distinguished. MFS is almost exclusively inherited in an autosomal dominant manner, although case reports have described rare recessive FBN1 mutations [4]. While most individuals with MFS have an affected parent, 25 percent or more of probands have MFS as the result of a de novo mutation. Most patients with the typical Marfan phenotype harbor various mutations involving the Fibrillin-1 (FBN1) gene [5-7]. However, FBN1 mutations also occur across a wide range of milder phenotypes that overlap the classic Marfan phenotype. (See 'FBN phenotypes' below.) In a minority of cases (less than 10 percent) with typical Marfan phenotype, no mutation in FBN1 is identified [3]. In some of these individuals, an inactivating mutation in a gene encoding for transforming growth factor-beta receptor (TGFBR) may be responsible.

Frequency:
There is a higher incidence of WPW in Marfan's syndrome than in the general population.

Medication:
Beta-blocker and calcium-antagonist therapy retard the aortic growth rate in children and adolescents with Marfan syndrome. Atenolol, a beta-blocker that is longer acting and more cardioselective than others, has largely replaced propranolol as the beta-blocker of choice. Experience with calcium antagonists is limited.

Asperger’s syndrome

Thomas Edison and Albert Einstein

History:

Asperger syndrome (AS), an autism spectrum disorder (ASD), is a relatively new diagnosis in the field of autism.[1] It was named in honor of Hans Asperger (1906–80), an Austrian psychiatristand pediatrician. An English psychiatrist, Lorna Wing, popularized the term "Asperger's syndrome" in a 1981 publication; the first book in English on Asperger syndrome was written by Uta Frithin 1991 and the condition was subsequently recognized in formal diagnostic manuals later in the 1990s.

Clinical diagnosis or characteristics:

Mental: Does the person seem to have an extreme ability to focus on a given task? So much so that the person obsesses over a given interest or subject? Does the person have a great memory, able to recall tiny details? These are often signs of a person with Asperger's. Remember, the founder of Asperger's described his first patients as "little professors," extremely knowledgeable within their chosen favorite...
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