This is an essay about Tuner's Syndrome a genetically transferred disease

Essay by pleczkowskHigh School, 11th gradeA+, March 2003

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In 1938 Dr. Henry Turner, an internist at the

University of Oklahoma, described what is now called

Turner's syndrome. Turner's syndrome is a relatively

common genetic disorder found in females affecting many

body systems. Although this disorder was described in

1938, it was not until 1959 that the technology was

available to determine the cause of this disorder.

Humans normally have a total of 46 chromosomes (which

are tiny, DNA-containing elements) that are present in

every cell of the body. DNA encodes genes, which specify

all the proteins that make up the body and control its

functions. There are 23 matched pairs of chromosomes in

every cell. Each cell contains 22 pairs of chromosomes

called autosomes that are the same in males and females.

The remaining pair of chromosomes, the X- and Y-

chromosomes, are not shaped similarly, and thus are not

matched in the same way as the autosomes.

The X- and Y-

chromosomes are called sex chromosomes. They are

responsible for the difference in development between males

and females. A Y-chromosome contains genes responsible for

testis development; and the presence of an X-chromosome

paired with a Y-chromosome will determine male development.

A female with normal genetic make-up has two X-chromosomes

in each of her cells, one which she received from her

father and one, which she received from her mother. Two X-

chromosomes are required for normal ovarian development in


The female with Turner's syndrome has only one X-

chromosome in each of her cells due to a nondisjunction

event during meiosis of her parents' gametes. A careful

examination of the genetic material, usually by means of a

blood sample, can confirm the diagnosis of Turner's

Syndrome. Depending on the degree of nondisjunction of her

parents' gametes, the genotype of Turner Syndrome can

vary. The...