(i) Oligopotency refers to stem cells that can differentiate into few cell types.
(ii) For example lymphoid or myeloid stem cells can differentiate into Band T cells but not RBC.

(i) The gene must be harmless to the patient.
(ii) Gene must be appropriately expressed.
(iii) Body's Immune system does not react to the foreign proteins produced by the new genes.

(i) Gene augmentation therpy :Insertion of DNA into the genome to replace the missing gene product
(ii) Gene inhibition therpy : Insertion of the anti sense gene which inhibits the expression of the dominant gene.

The DNA vaccine cannot cause the disease as it contains only copies of a few of the genes of the pathogen

Cancer, AIDS, multiple sclerosis, hepatitis C and herpes zoster

Yes but the amount of blood required for isolation of interferons is enormous. Thus they are produced by rDNA technology

The yeast Saccharomyces cerevisiae is more suitable for production of recombinant interferons than E.coli, since E.coli does not possess the machinery for glycosylation of proteins

The following criteria must be satisfied for patenting:
(I) The invention must be novel and useful;
(II) The product must be inventive and reproducible;
(III) The patent application should provide the full description of the invention and the invention must be patentable.

PCR technique can be used in the field of forensic medicine. A single molecule of DNA from blood stains, hair, semen of an individual is adequate for amplification by PCR. The amplified DNA is used to develop DNA fingerprint which is used as an important tool in forensic science. Thus, PCR is very useful for identification of criminals

Presence of pathogens like virus, bacteria, etc., is detected only when the pathogen produces symptoms in the patient. By the time the symptoms appear, concentration of pathogen becomes very high in the body. However very low concentration of a bacteria or a virus, even when the symptoms of the disease does not appear, can be detected by amplification of their nucleic acid. Thus PCR and ELISA help in early diagnosis

(i) Stem cell banking is the extraction, processing and storage of stem cells, so that they may be used for treatment in the future, when required.
(ii) Amniotic cell bank is a facility that stores stem cells derived from amniotic fluid for future use.
(iii) Cord blood banking is the extraction of stem cells from the umbilical cord during childbirth.

 Gene augmentation therapy involves insertion of DNA into the genome to replace the missing gene product.

It is a connective therapy to cure hereditary diseases and involves the transfer of a normal gene into a person's cells that carries one ormore mutant alleles. It is of two types
(i) Somatic cell gene therapy.
(ii) Germ line gene therapy 

Recombinant Hepatitis B vaccine is a subunit vaccine produced by cloning hepatitis B surface antigen (HbsAg) gene in the yeast saccharomyces cerevisiae. It is the first synthetic vaccine to be produced.