Tay-Sachs disease is caused by a defective gene on chromosome 15. When both parents carry the defective Tay-Sachs gene, a child has a 25% chance of developing the disease. The child must receive two copies of the defective gene -- one from each parent -- in order to become sick.
Enacted by law in 2013, the newest symbols of North Carolina are the state art medium, clay; the state fossil, the Megalodon teeth; the state frog, the Pine Barrens tree frog; the state marsupial, the Virginia opossum; and the state salamander, the Marbled salamander.
Report Abuse. According to Memory Alpha It has never been canonically established what the letters NCC or NX stand for, but in the 23rd and 24th centuries, NX (not to be confused with NX class) seemed to be used to designate experimental or prototype starships while NCC designated normal production vessels.