Flynn–Aird syndrome
Flynn–Aird syndrome |
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Flynn-Aird Syndrome is a rare, autosomal dominant, hereditary degenerative neurological disease involving defects in the nervous, auditory, skeletal, visual, and endocrine systems. It encompasses numerous symptoms, bearing striking similarity to known syndromes including: Werner syndrome, Cockayne syndrome and Refsum syndrome.[1]
The onset of Flynn-Aird Syndrome typically occurs between ten and twenty years of age, however, the earliest case was diagnosed at age seven. As the syndrome progresses, initial symptoms tend to intensify and new symptoms become apparent. Despite the intensity of new symptoms and disease progression, Flynn-Aird syndrome does not appear to shorten life expectancy. The disease is characterized by early-onset dementia, ataxia, muscle wasting, skin atrophy, and eye abnormalities. It has the potential to cause cataracts, retinitis pigmentosa, myopia, dental caries, peripheral neuropathy, deafness, and cystic bone changes. This syndrome was first discovered in the early 1950s by American neurologists P. Flynn and Robert B. Aird who analyzed one family lineage inheritance pattern of this disease. [1]
Pathophysiology
The exact pathophysiological mechanism of Flynn-Aird Syndrome is unknown. However, several theories are in place with regards to the nature of this disease including the presence of a genetically defective enzyme involving a neuroectodermal tissue constituent, which provides evidence for the late onset of the condition, the intricate findings, the varied nature of the disorder, as well as the genetic incidence. In addition, some aspects of the condition may be linked to a suppressing (S) gene due to the fact that only a small amount of stigmata appeared but the defects were transmitted in the family studied. Other abnormalities may be due to endocrine system diseases. [2]
Symptoms
Individuals with this syndrome typically develop normally until they reach the second decade of their lives but the earliest observed onset of Flynn-Aird symptoms was observed at age seven. The first defect observed in individuals who suffer from this condition affects the auditory system and is known as bilateral nerve deafness. Another early symptom was the development of myopia, which affects an individual’s vision. In addition to bilateral nerve deafness and myopia, other symptoms that plagued infected individuals early on in disease progression include ataxia, muscle wasting, severe peripheral neuritic pain sometimes accompanied by elevated spinal fluid protein, and joint stiffness.[3]
The central nervous system (CNS) is inflicted in this condition because deficits in the cerebral cortex indicate signs of mental retardation even though psychological observations appeared relatively normal for individuals studied. Atypical epilepsy was also a common feature of CNS malfunctioning including aphasia expressions, blurred vision, and numbness of the face and limbs. [4]
In the third decade of the condition, suffers endured the restriction of visual fields, night blindness, and eventually severe complete blindness. Individuals also developed visual problems including retinitis pigmentosa, and bilateral cataracts. Individuals with this syndrome had many physical deformities including skeletal, epidermal, and subcutaneous abnormalities. The skeletal problems were indicative of the kyphoscoliotic type and they follow muscle wasting and peripheral neuritis. Osteoporosis is also observed in many cases. Skin and subcutaneous atrophy is common as well as skin ulcerations due to inability of the skin to heal. One of the final manifestations of disease is baldness. [5]
There was no evidence that the progression of Flynn-Aird disease shortened life but the terrible conditions make for a very difficult life. [6]
Genetics
One family of 68 individuals over 5 generations was studied and the prevalence of disease among the family members suggests that it is indicative of dominant inheritance. This is supported by the fact that the disease failed to skip generations even in the absence of intermarriages. The current findings suggest that the cause of the disease could be narrowed down to one enzymatic defect that is involved in the development of neuroectodermal tissue. The other symptoms that arise such as bone defects and diabetes may be secondary to this enzymatic defect. [7]
History
P.Flynn and Robert B. Aird observed this neuroectodermal syndrome after studying one family whose members suffered a number of neurological symptoms that were consistent from generation to generation. A number of the symptoms overlapped with several known neurological diseases such as Werner syndrome, Refsum syndrome, and Cockayne syndrome, which could be indicative of a similar origin of disease. About 15% of family members exhibited full-blown symptoms characteristic of the disease while others showed some symptoms that overlapped with the general clinical manifestation of the syndrome. [8]
![](http://upload.wikimedia.org/wikipedia/commons/thumb/e/e1/Autodominant.jpg/220px-Autodominant.jpg)
References
- ^ a b Flynn P, Aird RB (1965). "A neuroectodermal syndrome of dominant inheritance". J. Neurol. Sci. 2 (2): 161–82. doi:10.1016/0022-510X(65)90078-X. PMID 5878601.
- ^ Flynn P, Aird RB (1965). "A neuroectodermal syndrome of dominant inheritance". J. Neurol. Sci. 2 (2): 161–82. doi:10.1016/0022-510X(65)90078-X. PMID 5878601.
- ^ Flynn P, Aird RB (1965). "A neuroectodermal syndrome of dominant inheritance". J. Neurol. Sci. 2 (2): 161–82. doi:10.1016/0022-510X(65)90078-X. PMID 5878601.
- ^ Flynn P, Aird RB (1965). "A neuroectodermal syndrome of dominant inheritance". J. Neurol. Sci. 2 (2): 161–82. doi:10.1016/0022-510X(65)90078-X. PMID 5878601.
- ^ Flynn P, Aird RB (1965). "A neuroectodermal syndrome of dominant inheritance". J. Neurol. Sci. 2 (2): 161–82. doi:10.1016/0022-510X(65)90078-X. PMID 5878601.
- ^ Flynn P, Aird RB (1965). "A neuroectodermal syndrome of dominant inheritance". J. Neurol. Sci. 2 (2): 161–82. doi:10.1016/0022-510X(65)90078-X. PMID 5878601.
- ^ Flynn P, Aird RB (1965). "A neuroectodermal syndrome of dominant inheritance". J. Neurol. Sci. 2 (2): 161–82. doi:10.1016/0022-510X(65)90078-X. PMID 5878601.
- ^ Flynn P, Aird RB (1965). "A neuroectodermal syndrome of dominant inheritance". J. Neurol. Sci. 2 (2): 161–82. doi:10.1016/0022-510X(65)90078-X. PMID 5878601.
External links
- Flynn Aird syndrome at NIH's Office of Rare Diseases