Complex sentence: For example, the fatal Tay-Sachs disease arises as genetic defects leads to no functional hexosaminidase A produced, causing GM2 to accumulate in lysosomes, ultimately the ganglion cells in the nervous system swells enormously, disturbing the normal functions of neurons.
Split into simpler sentences: For example, the fatal Tay-Sachs disease arises as a genetic defect which leads to no functional hexosaminidase A produced, causing GM2 to accumulate in lysosomes. Ultimately the ganglion cells in the nervous system swell enormously, disturbing the normal functions of neurons.