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Gene Dosage - Charcot-Marie-Tooth Disease | Experts in CMT

Gene Dosage

How many copies of a gene, and how much product

Gene dosage is the number of copies of a gene and the amount of product they make. Disease can result from too little dosage (haploinsufficiency) or too much (a duplication or overexpression). The clearest CMT example is CMT1A, caused by a duplication of PMP22 that adds a third copy and overexpresses the protein; the reciprocal deletion causes the milder HNPP.

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