Genetics & Biotechnology


Punnet Square I
Punnet Square II

Punnet Square III
Making Babies

Family Pedigree with Traits
Traits Lab
Mapping Traits
Protein Synthesis

Genetic SLC
DNA Replication

Protein Synthesis
DNA Fingerprinting

Genetics Facts

Student Objectives
Protein Synthesis
DNA Fingerprinting
Genetic Engineering

Genetics Sites


Double Helix, by

Return SAS Home
e-mail Kevin C. Hartzog

Genetics & Biotechnology


When in 1973, Stanley Cohen and Herbert Boyer combined the genetic material of a frog and a bacteria, the scientific community had stepped into a new realm, biotechnology. Today, biotechnology have moved from the laboratory, to the market. With bioengineer corn, tomatoes, cotton, and rice grown by farmers, we find ourselves in a new era.

On paper, the technique the Cohen and Boyer began is simple. Take the RNA of a bacteria. Slice out a gene that you have an interest in. Insert that gene into the DNA of a frog's egg cell. But the trick lays in finding the right segment of gene to cut, and the proper location in which to splice it.

Gene splicing has gone through dramatic changes, and the procedures are far more accurate now. In fact, there are several methods in use, but they all share a few common steps.

  1. Cleaving DNA. The DNA in which you are interested in is cut into fragments using restriction enzymes. Restriction enzymes locates a sequence of nucleotides, then cuts the DNA at that place.
  2. Producing recombinant DNA. The DNA segment cut by the restriction enzyme is put into the DNA of a vector, an agent used to carry the DNA segment into another cell. Viruses and plasmids are the most common vectors used. Viruses naturally insert their genetic material into cells. Plasmids are circular DNA found in bacteria that can replicate itself independently from the rest of the bacteria's genetic material.
  3. Cloning cells. A culture of bacteria is infected with the vectors' DNA segments, then grown, and reproduced asexually. This is cloning.
  4. Screening cells. Those bacterial cells that have received the gene you are interested in are identified and isolated.