Clonning

– Dolly has been clone taken from her mother’s udder.
– Unfertilized egg cell with nucleus removed were fused with the cell from the udder
– Fused cell was stimulated to divide and implanted into a surrogate mother.
– Polly
• Single diploid cell originating from adult sheep was altered (human gene coding for blood cloting factor was introduced) and the cell was fused with denucleated egg cell. The fused cell was stimulated to divide and implated into surrogate mother.
• Lamb contains the human gene in every cell of her body.

• Gene Therapy for severe combined immunodeficiency (SCID)

• Gene therapy succeeded for 15 French baby boys who suffered from SCID, called X-linked SCID, because it is caused by a mutated gene encoding a subunit — called γc (gamma-c) — of the receptor for several interleukins, including interleukin-7 (IL-7).

• IL-7 is essential for converting blood stem cells into the precursors of T cells. Boys with X-linked SCID do not develop ********al immune response system.

• Doctors isolated blood stem cells from the bone marrow of each boy;
treated the cells with a vector containing the normal gene for the γc interleukin receptor subunit; returned the treated cells to each donor.

• The results: Now after as long as three and one-half years, these boys are able to live normal lives at home instead of inside a sterile "bubble"; have normal (with two exceptions*) numbers of T cells .