Definitions

Allograft

Transplanted organ from a different individual inside species (e.g. from donor human to recipient human).

Antisense RNA

A short segment of DNA, which binds to complementary messengerRNA so that the encoded protein is not produced.

Expression

A gene manifests itself by the gene product it encodes. The product is observed in a cell or secreted from a cell.

Oligonucleotide

A short, defined sequence of nucleotides joined together in the typical phosphodiester linkage.

Promoter

The site on the DNA molecule at which an enzyme called RNA polymerase binds to initiate gene transcription with the formation of messenger RNA.

Recombinant DNA

The altered DNA that results from the insertion of a sequence of deoxynucleotides not previously present into an existing molecule of DNA by enzymatic or chemical means.

Replication

Multiplication, a process which duplicates e.g. DNA before cell division.

Ribozyme

Catalytic RNA, which cleaves certain target RNA and thus prohibits the gene function.

Transduction

Insertion of the desired exogenous gene into the proper cell (usually by retrovirusvector).

Transfection

Insertion of the desired exogenous gene into the proper cell by viral or physical methods.

Transgene

A foreign new gene introduced into a cell.

Vector

A vehicle plasmid or bacteriophage into which foreign DNA can be introduced for the purposes of gene transfer.

Xenograft

Transplanted organ from different species (e.g. from pig to ­human).