With a number of hotspots, either autism and schizophrenia were observed depending on the copy-number variation (CNV) at that location.Statistical research showed that schizophrenia is more common in combination with 1q21.1 deletion syndrome. On the other side, autism is significantly more common with 1q21.1 duplication syndrome. Further research confirmed that the odds on a relation between schizophrenia and deletions at 1q21.1, 3q29, 15q13.3, 22q11.21 en Neurexin 1 (NRXN1) and duplications at 16p11.2 are at 7.5% or higher. Common variations in the BCL9 gene, which is in the distal area, confer risk of schizophrenia and may also be associated with bipolar disorder and major depressive disorder.Research is done on 10–12 genes on 1q21.1 that produce DUF1220-locations. DUF1220 is an unknown protein, which is active in the neurons of the brain near the neocortex. Based on research on apes and other mammals, it is assumed that DUF1220 is related to cognitive development (man: 212 locations; chimpanzee: 37 locations; monkey: 30 locations; mouse: 1 location). It appears that the DUF1220-locations on 1q21.1 are in areas that are related to the size and the development of the brain. The aspect of the size and development of the brain is related to autism (macrocephaly) and schizophrenia (microcephaly). It has been proposed that a deletion or duplication of a gene that produces DUF1220-areas might cause growth and development disorders in the brain Another relation between macrocephaly with duplications and microcephaly with deletions has been seen in research on the HYDIN Paralog or HYDIN2.
Through examinations in families it was found that there is a family connection to the occurrences, which leads to the conclusion that there is a genetic predisposition for it; for example, patients with folliculitis decalvans could have a hereditary different opening of the hair follicle that could facilitate the lodging of the bacteria. Immunologically, another possibility is that especially strong intercellular fixation protein ICAM-1 contributes to inflammation with its strong effect of attracting white blood cells such as granulocytes and lymphocytes. Diagnosis
Management
Some sufferers have found that a daily intake of MSM helps relieve the inflammation and scarring that comes with chronic Folliculitis decalvans. Epidemiology
This disorder was first described by Charles-Eugène Quinquaud in 1888. He isolated bacteria from the hair follicles of affected patients and introduced them in rats, mice and rabbits, with no result. In 1905 it was then differentiated from other scarring alopecias and the name Folliculitis decalvans, that remains current, was introduced. About 11% of the occurrences of scarring alopecias are of this type. Men are more commonly affected than women and its appearance is usually between the late teens and middle adult years. According to studies in the United States, African Americans are more frequently affected than White Americans. See also
Cicatricial alopecia

References


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