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.
The classical form of Tay-Sachs disease occurs during infancy; an adult form (late-onset Tay-Sachs disease) may occur anytime from adolescence to the mid 30's. Tay-Sachs disease is inherited as an autosomal recessive trait. The disorder results from changes (mutations) of a gene known as the HEXA gene, which regulates production of the hexosaminidase A enzyme. The HEXA gene has been mapped to the long arm (q) of chromosome 15 (15q23-q24).