Q.16 Somatic cell gene transfer is used for

P. Transgenic animal production
Q. Transgenic diploid cell production
R. In-vitro fertilization
S. Classical breeding of farm animals

• (A) P, R and S
• (B) P, Q and R
• (C) P and R
• (D) P only

  Somatic cell gene transfer modifies non-reproductive body cells, distinct from germline methods affecting gametes. Commonly via viral vectors or electroporation, it targets therapeutic gene addition/correction. This MCQ tests its core biotechnology application.

  Correct Answer: (D) P only
  Somatic cell gene transfer is primarily used for transgenic animal production through somatic cell nuclear transfer (SCNT). Donor somatic cells are genetically modified in vitro, then used to create cloned transgenic animals like Dolly derivatives.

  Somatic Cell Gene Transfer Mechanism

  In SCNT, fibroblasts/somatic cells receive transgenes via transfection. Modified cells (expressing selectable markers) serve as nuclear donors for enucleated oocytes. Reconstructed embryos develop into fully transgenic animals where every cell carries the modification—unlike random pronuclear microinjection.

  Explanation of All Options

  Each technique’s relation to somatic cell gene transfer:

  • P. Transgenic animal production
    Correct. SCNT uses genetically engineered somatic cells as nuclear donors, ensuring 100% transgenicity vs. microinjection’s ~5% efficiency.

  • Q. Transgenic diploid cell production
    Incorrect. Creates modified cell lines (not animals); “transgenic” typically denotes whole organisms.

  • R. In-vitro fertilization
    Incorrect. IVF fertilizes oocytes normally; no somatic cell genetic modification involved.

  • S. Classical breeding of farm animals
    Incorrect. Traditional selective breeding; no molecular gene transfer.

  Code	Application	Uses Somatic Cell Gene Transfer?	Method Example
  P	Transgenic animal production	Yes	SCNT (Dolly method)
  Q	Transgenic diploid cell production	No	Cell culture only
  R	In-vitro fertilization	No	Gamete fusion
  S	Classical breeding	No	Natural selection

  Biotechnology Significance

  SCNT revolutionized transgenics—gene-targeted knockouts (e.g., PrP-/- sheep), disease models, xenotransplantation pigs. Unlike germline methods, somatic changes aren’t heritable, raising fewer ethical concerns. Essential for biopharming (human proteins in milk) and conservation cloning.

  Key exam takeaway: Somatic cell gene transfer = SCNT transgenic animal production.