Telechelic polymer. A telechelic polymer or oligomer is a prepolymer capable of entering into further polymerization or other reactions through its reactive end-groups. It can be used for example to synthesize block copolymers. By definition, a telechelic polymer is a di-end-functional polymer where both ends possess the same functionality. Where the chain-ends of the polymer are not of the same functionality they are termed di-end-functional polymers.
The cause of Tay-Sachs disease is a genetic defect (mutation) that is passed from parent to child. This genetic defect is located in the HEXA gene, which is found on chromosome 15.The HEXA gene makes part of an enzyme called beta-hexosaminidase A, which plays a critical role in the nervous system.he cause of Tay-Sachs disease is a genetic defect (mutation) that is passed from parent to child. This genetic defect is located in the HEXA gene, which is found on chromosome 15.
Progressive damage caused by the buildup of GM2 ganglioside leads to the destruction of these cells, which causes the signs and symptoms of Tay-Sachs disease. Most of the known HEXA mutations result in a completely nonfunctional version of beta-hexosaminidase A. These mutations cause the severe form of Tay-Sachs disease, which appears in infancy. Other mutations reduce but do not eliminate the activity of beta-hexosaminidase A; these genetic changes are responsible for the less severe forms of Tay-Sachs disease, which appear later in life.