Treatment of genetic disorders by introducing proper genes into cells of the target organ, is called gene therapy. the gene used in gene therapy is often called gene drug. The drug gene may be introduced into somatic cells or germ cells or zygotes.
If genes are introduced into somatic cells, it is called somatic cell gene therapy. If genes are introduced into eggs or zygotes, it is called germline gene therapy. Gene therapy is used to cure asthma, non Hodgkin’s lymphoma, melanoma etc.
Somatic Therapy vs Germline Therapy
Genes are introduced into somatic cells.
Genes are introduced into germ line cell and will get distributed in both germ cells and somatic cells.
Changes are confined to the recipient.
Changes will be passed to the future generations.
Genes are tissue specific in most instances(in their expression) although not location specific in many. In many instances, it may not be possible to reconstitute normal level and tissue distribution.
High frequency of insertional mutations are observed in this process and cause teratogenic consequences.
Technical expertise for somatic cell manipulations in vitro introduction of gene of interest and replanting somatic cells in body to make them functional is developed.
There are still many technical difficulties in introduction of genes into germ cells.
No ethical issues attached.
Ethical problems to be answered and precludes its use.