Page 65 - Cell biology PDG 2024

Examples of gene therapy:
1) Type 1 diabetes mellitus (T1DM)
It is a disease that results from the autoimmune destruction of β cells
of the pancreas that are responsible for the production of insulin
leading to elevated blood sugar level
Scientists insert recombinant insulin in mouse and rat models of type 1
diabetes mellitus using lentivirus as a viral vector for treatment of this
disease and the results was promising

Figure 30: production of recombinant insulin

2) Adenosine deaminase (ADA) deficiency
There was a girl named Ashanti DeSilva, born in 1986, when she was 26-
months-old she was diagnosed with a rare genetic disease called SCID
(severe combined immune deficiency disease) that is due to adenosine
deaminase (ADA) deficiency. The disease is characterized by the
disturbed development of functional T cells and B cells due to mutation
and defect in adenosine deaminase (ADA) enzyme, necessary for the
breakdown of purines. Lack of ADA causes accumulation of dATP. This
metabolite will inhibit the activity of ribonucleotide reductase, the

٦٤