The Eighties in America - Salem Press (2009)

procedure was used to identify the locus of numer-
ous other genetic mutations.

Human Genome Project Mapping the entire se-
quence of nucleotides in the human genome long
represented the holy grail of human genetics. Prior
to the 1980’s, the sheer number of base pairs consti-
tuting the genome precluded analysis at that level.
During the 1970’s, however, techniques were devel-
oped that allowed for the sequencing of large seg-
ments of DNA, including the human genome. In
1975, Fredrick Sanger first published a method for
sequencing DNA; the procedure was quickly super-
seded by one developed by Allan Maxam and Walter
Gilbert that same year. Improvements in computer
technology at the same time allowed for the process
of sequencing to be carried out in a rapid and highly
efficient manner.
In 1981, molecular techniques accomplished the
sequencing of the first genome found in human
cells: mitochondrial DNA. Only the year before had
it been found that one’s mitochondria and mito-
chondrial DNA are inherited solely from one’s
mother. Though the mitochondrial DNA consisted
of only 16,500 base pairs, the demonstration that se-
quencing was practical on that scale set in motion
the idea of applying the same technique to the ge-
nome as a whole. Consequently, in 1984 and 1985,
Robert Sinsheimer, Nobel laureate Renato Dul-
becco, and others began lobbying for funds to begin
the project. Subsequently, the National Research
Council, a component of the prestigious National
Academy of Sciences, established a committee to set
the program in motion.

Forensic Analysis Because each person’s DNA is
unique, incubating a person’s DNA with restriction
enzymes generates a sequence of fragments unique
to that individual. This technique is known as “re-
striction fragment length polymorphism” (RFLP).
In 1984, RFLP was successfully used to identify indi-
viduals by their so-called DNA fingerprint. The same
technique was also used to determine whether dif-
ferent persons were genetically related. RFLP was
quickly adapted to use by police conducting forensic
investigations and by people attempting to establish
a child’s paternity. DNA fingerprinting was initially
used in 1984 to identify the families of kidnapped
children in Argentina. In 1989, DNA fingerprinting
was used for the first time to identify the suspect in a
murder case in the United Kingdom.

Impact During the 1980’s, theoretical genetic

knowledge and recently developed practical tech-

niques were combined and applied to the study of

human genes and DNA. Tests for some genetic mu-

tations were developed, the Human Genome Proj-

ect was begun, and DNA fingerprinting became a

practical reality. Thus, geneticists transformed the

fields of medicine and law enforcement, as well as

contributing to the general understanding of hu-

man heredity and the role and functioning of genes

on the most basic, molecular level.

Further Reading

Hartl, Daniel, and Elizabeth Jones.Genetics: Analysis

of Genes and Genomes. 6th ed. Sudbury, Mass.:

Jones and Bartlett, 2004. Reviews both classical

and modern genetics, including the development

of research techniques during the period be-

tween the 1970’s and 2000.

Khoury, Muin, et al.Fundamentals of Genetic Epidemi-

ology. New York: Oxford University Press, 1993.

Applies the role of genetic factors with develop-

ment of disease in human populations. Includes a

summary of genetic techniques.

Ott, Jurg.Analysis of Human Genetic Linkage. Balti-

more: Johns Hopkins University Press, 1999.

Summary of techniques used to determine ge-

netic loci as applied to human genetic diseases.

Richard Adler

See also Bioengineering; DNA fingerprinting; Fe-

tal medicine; Health care in the United States; Medi-

cine; Science and technology.

Gentrification

Definition Changes in the population of urban

districts resulting in the raising of rents and

property values

Gentrification refers to changes in urban centers in terms of

populations, demographics, character, and culture. It entails

wealthier people moving into urban centers and changing

the housing stock. The process is most often characterized by

social, socioeconomic, and often racial tensions between

original residents and those who have moved to these neigh-

borhoods.

Through the latter half of the twentieth century, the

majority of American cities came to be characterized

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Gentrification The Eighties in America