CONCEPTS IN BIOLOGY

PART III. MOLECULAR BIOLOGY, CELL DIVISION, AND GENETICS

11. Applications of Biotechnology

Thinking of Preserving Baby’s Cells?

Banking on future medical treatments—skepticism required.

How young can you be to donate blood? Normally, a baby’s umbilical cord is discarded after birth. However, blood that remains in the cord contains stem cells that can be collected and preserved in hopes that it may be useful in the future. Stem cells have the ability to develop into any of your cells. Would you like to have some of your child’s embryonic stem cells preserved so that they might be used to cure illness or repair injury? If the child experiences tissue or organ problems due to damage, disease, age, or genetic defects, these preserved cells might be used to generate tissues to repair or replace the damage. It is thought that these stem cells have the potential to be cloned and used to treat such conditions as: cancer, brain injury, juvenile diabetes, renal failure and spinal cord injuries. The cost of private cord blood banking is about $2,000 for collection and $125 per year for storage.

While at first glance this sounds to be “the way to go” in assuring that your child’s future health problems may be dealt with efficiently, the procedure is controversial. Even though public cord blood banking is supported by the medical community, the American Academy of Pediatrics 2007 Policy Statement on Cord Blood Banking noted that physicians should be aware of unsubstantiated claims of private cord blood banks. Other aspects of this controversy center on issues and such facts as:

ü  The likelihood of using your own stem cells is 1 in 435.

ü  The European Union Group on Ethics states the legitimacy of commercial cord blood banks for such use should be questioned because they sell a service that presently has no real therapeutic value.

ü  Cord blood cells have the same genes as the donor and cannot be used to treat genetic diseases of the donor.

• What are stem cells?

• What does it mean to clone cells?

• Would you buy into a cord blood donation program?

ü  Background Check

Concepts you should already know to get the most out of this chapter:

• All organisms use the same genetic code to make proteins (chapter 8)

• DNA codes for genetic information that codes for the cell’s proteins (chapter 8)

• Proteins influence how the organism or the cell looks, behaves, and functions (chapter 10)

11.1. Why Biotechnology Works

The discovery of DNA’s structure in 1953 opened the door to a new era of scientific investigation. Biotechnology is a collection of techniques that provide the ability to manipulate the genetic information of an organism directly. As a result, scientists can accomplish tasks that were not feasible just 60 years ago. The field of biotechnology has enabled scientists to produce drugs more cheaply than before; to correct genetic mutations; to create cells that are able to break down toxins and pollutants in the environment; and to develop more productive livestock and crops. Biotechnology promises more advances in the near future.

The key to understanding biotechnology is understanding the significant role that DNA plays in determining the genetic characteristics of an organism. In the cell’s nucleus, chromosomes are made of DNA and histone proteins. The genetic information for the cell is the sequence of nucleotides that make up the DNA molecule. Genes are regions of the DNA’s nucleotide sequence that contain the information to direct the synthesis of specific proteins. In turn, these proteins produce the characteristics of the cell and organism when the gene is expressed by transcription and translation.

The nearly universal connection among DNA, protein expression, and the organism’s phenotype is central to biotechnology. If an organism has a unique set of phenotypes, it has a unique set of DNA sequences. The more closely related organisms are, the more similar are their DNA sequences.

11.1. CONCEPT REVIEW

1. Why is the word directly so important to the understanding of the definition of biotechnology?

2. Why can DNA in one organism be used to make the same protein in another organism?