in the x direction, the water wants to flow in that direction) For a given hydraulic. conductivity, the vertical flow rate depends on the sum of the gravitational potential energy. gradient per unit weight of water (dz/dz =1) and the vertical gradient in soil water pressure.
Origin and spread of the 1278insTATC mutation causing TayâSachs disease in Ashkenazi Jews: Genetic drift as a robust and parsimonious hypothesis. Human Genetics 114 (4): 366â376. pmid 14727180.
Mutations in the Tay-Sachs Chromosome. Tay-Sachs disease is caused by mutations in the HEXA gene. More than 95 mutations that cause the disease have been identified. These mutations reduce or eliminate the activity of the enzyme beta-hexosaminidase A, preventing the normal breakdown of GM2 ganglioside in the brain and spinal cord.