The Challenges and Impact of Human Genome Research for Minority Communities

proceedings from a conference presented by
Zeta Phi Beta Sorority, Inc., National Educational Foundation
July 7-8, 2000, Philadelphia, PA

Zeta Background
Acknowledgments
Introduction
Foreword
Zeta NEF Purpose

Conference
Conference Mission
Conference Objectives
Research Plans
Conference Agenda
Conference Summary
Workshop I Summary
Workshop II Summary
Workshop III Summary
What's Next?
Photographs
Human Genome News article

Presenters
Dr. Aristides A. Patrinos
Dr. John Quackenbush
Dr. Georgia M. Dunston
Dr. Mary Kay Pelias
Dr. Fatimah Jackson
Dr. Christopher Adams
Dr. Rosalind P. Hale
Dr. Margaret C. Werner-Washburne
Rev. Dr. Deborah P. Wolfe
Dr. Jeroo S. Kotval
Betty K. Mansfield
Issie L. Shelton Jenkins, Esq.
Phyllis Griffin Epps, Esq.
Dr. Kathryn T. Malvern

Contact Information
Board of Managers
Presenters
National Educational Foundation

The exponential growth of our knowledge of the human genome has confirmed what man has known intuitively for eons: genetic factors in health and disease affect all human groups in countless ways. Most of our genes contribute to "normal variation," or the spectrum of characteristics that make all of us human, yet all unique. The concept of normal variation includes such traits as intelligence, color, and stature and body form, all of which are difficult to define and quantify. While we all know that genes are very much involved in the determination of these characteristics, we also know very little about exactly how many genes are involved or what those genes actually do. In addition to all of our normal traits, genes also contribute to characteristics related to health and disease. Some health problems are directly controlled by single genes that are really identifiable, while other health problems are controlled by complex interactions of many genes throughout the human genome. Some hereditary health problems are deadly, while others are amenable to medical treatment, or surgical treatment, or even to dietary or other environmental manipulations. As we continue to explore our genes, we are learning that we will realize immense benefits from the new genetic technologies and the development of new treatment protocols.

As a prototype of how specific genetic problems affect specific human groups, the populations of Louisiana offer several excellent examples. At least 6 populations have been documented as relatively closed groups. These "isolates" include the Scotch-Irish of the Central Hills and the Delta Blacks I the north, the Ten Milers in the center of the state, the Scotch-Irish of the Florida parishes, the Houmas Indians in the south, and the French Acadians. Each of these groups is characterized by the unique incidence of specific genetic problems that reflect the genealogical and genetic history of the original settlers in separate geographical areas. The populations of Louisiana represent a microcosm of populations around the world, each with its own genetic endowment.

The scope of hereditary health problems is immense. These problems reflect the adage that "anything that can go wrong will go wrong," because every physiological process and every biochemical conversion is subject to malfunction. Many problems are caused by mutations that affect the membranes of cells in various tissues and organs so that nutrients or hormones can no longer attach to cells or be transported across the membranes to the places where they should function. Other genetic diseases are the result of mutations that affect the synthesis or the activity of enzymes that drive the thousands of biochemical conversions that characterize normal metabolism. Such enzyme deficiencies may result in the a accumulation of substances that can be toxic to the system if they are present in greater than normal amounts, as we see most dramatically in the array of "storage diseases" that occur more frequently in some ethnic groups than in others. In addition to a plethora of enzymopathies, the synthesis and function of structural proteins is subject to mutational changes, with the result that the normally strong fibers of muscle, tendons, ligaments, bone, and connective tissue may be weak and prone to collapse. Proteins associated with blood and oxygen transport are likewise subject to deleterious mutations that are expressed in a variety of anemias and other deficiencies. Genetic changes are also implicated in a vast number of sensory deficits that result in blindness, deafness and the ability to sense pain. Finally, we are rapidly learning that genes account for cancer and a spectrum of behavioral and psychiatric traits. The array expands daily, as does our potential for relieving the burden of genetic disease and disorders.

Over the past half century, research in human and medical genetics has focused on finding and characterizing genes that determine our normal traits as well as those hereditary variations that may lead to serious compromise of health and personal function. Numerous approaches to finding our genes are described as gene mapping, which entails family studies that show how a gene is transmitted through successive generations of large families. One approach to these studies involves tracking the "unknown" gene as it is transmitted with another gene whose position in the genome is already known. Once the chromosomal location of a gene is determined, various molecular techniques permit the detailed examination of DNA in the region until the gene itself is identified and is molecular sequence of nucleotides is elucidated. This sequence is then examined to determine the nature of the protein that is coded in the DNA nucleotides, with every three nucleotides coding for one of the 20 amino acids that determine protein structure. Once the amino acid sequence of the protein product is determined, the protein can be examined for its normal function and any alterations in structure that result from mutations, or changes, in the nucleotide sequence of the DNA.

With the molecular basis of DNA and protein delineated, new clinical approaches may be sought to treat – or even cure – some genetic diseases. One approach to treatment is to supply the gene product to the patient whose body is unable to produce the product. The isolation of the gene that codes for the structure of human insulin, for example, permitted the insertion of that gene into bacterial cells, which then became microscopic factories for producing human insulin that could be concentrated and administered to patients with diabetes. Another molecular approach to treatment is insertion of the isolated gene into the cells of a patient so that these cells can then produce the product that the patient was unable to manufacture because of a particular inborn genetic deficiency. This approach has been dramatically successful in the treatment of severe combined immune deficiency, or SCID, when bone marrow cells of patients are removed from the body and engineered to contain the gene that the patient lacks. Once the engineered cells are returned to the patient’s body and produce the formerly absent protein product, the patient may experience a dramatic upswing in immune function and general health. These are but two examples of the progress that clinical genetics and biomedical research are now offering to the human population, and many more can be expected in the not too distant future.

In spite of the great advantages that the Human Genome Project is conferring on man, our efforts are tempered by deliberation and caution among clinicians and laboratory scientists. Geneticists think carefully about the potential pitfalls in the applications of the new genetic technologies. They are dedicated to bringing advantages to the human population, while they simultaneously grieve the negative consequences of unexpected experimental outcomes. They continuously search for benefits in health and health care, while they simultaneously abhor the use of the new technologies for purposes of vanity or genetic enhancement. Geneticists seek advantages for man across all human groups, while they simultaneously guard our genetic legacy and our genetic future.