Question: Do you know any DNA diseases that aren't hereditary? If so, do you have any idea why they aren't?

Lilian Hunt answered on 10 Mar 2014:

DNA diseases and disorders are caused by a change in the DNA so in most cases it is possible for you to inherit them from your parents. Sometimes, when an embryo is developing into a baby in the womb, a mutation can randomly occur very early on and cause a genetic disorder that is new and not inherited. That child can then pass this onto its children when it eventually becomes an adult.

There can also be instances where in a cell in your body a random mutation can occur later in life. As your cells are constantly growing, dividing and dying, there are many chances for this to happen. Now sometimes that mutation can cause problems, and most often this problem is cancer. Cancer is actually the result of genetic mutations in cell that cause them to grown abnormally and divide many more times then normal. The actual cancer itself isn’t hereditary but is the result of a change in DNA in those specific cells.