Possible Gene Manipulation for Diabetes Cure

First lets distinguish the types of diabetes without going into much detail. Type 1 results when the body's immune response destroys the cells responsible for producing insulin these cells are called beta cells. Type 2 occurs when your body can't effectively keep up with the insulin demands of your body.  

With diabetes type 1 and 2 on the rise within the United States and throughout the world, scientists are looking around every corner to find a way to either prevent or cure diabetes. Dr. Francesca and her team from Max Delbruck Center for Molecular Medicine have found a way to reprogram liver cells into pancreatic beta cells in mice. This reprogram process occurs by introducing additional copies of the TGIF2 gene found on chromosome 2 of mice which reprograms the liver cells to take on an unspecialized state and stimulates the development of liver cells into pancreatic beta cells.

Although this study was not done on humans, progress and a new discovery has been made. This research brings genetic therapy for human diabetic patients a step closer for a cure. This is amazing research since so many lives are restricted by this disease. With the continuous study of the TGIF2 gene a cure may be within the near future.

The interesting part of this discovery for me that leaves me with a few questions is with the introduction of an increased amount of a certain gene would this lead to other mutations and to what degree? Would the mutations if any influence the degree to which other genes are expressed?
https://www.sciencedaily.com/releases/2017/02/170213083736.htm
http://www.genecards.org/cgi-bin/carddisp.pl?gene=TGIF2