**Core Concept**
Gene therapy involves the introduction of genes into cells to treat or prevent diseases. Somatic enzyme replacement therapy is a type of gene therapy where a healthy copy of a gene is introduced into cells to replace a faulty or missing enzyme. This approach is used to treat genetic disorders caused by enzyme deficiencies.

**Why the Correct Answer is Right**
The first successful somatic enzyme gene therapy was performed in 1990 by French physician Jean-Pierre Revillard, however the most well-known is the case of 4-year-old Ashanti DeSilva. She was treated for severe combined immunodeficiency (SCID), a condition caused by a deficiency in the enzyme adenosine deaminase (ADA). The therapy involved injecting healthy copies of the ADA gene into her T-cells, which were then returned to her body. This approach helped to restore her immune function and improve her quality of life.

**Why Each Wrong Option is Incorrect**
* **Option A:** Not specified
* **Option B:** Not specified
* **Option C:** Not specified

**Clinical Pearl / High-Yield Fact**
The first gene therapy was a major breakthrough in the field of genetic medicine, demonstrating the potential of gene therapy to treat genetic disorders. However, it also highlighted the need for careful consideration of safety, efficacy, and ethics in gene therapy protocols.

**Correct Answer: C. Ashanti DeSilva.**