CD-ROM Today 1996 January/CD-ROM Today 1996 January.iso/dp/0429/04297.txt

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$Unique_ID{BRK04297}
$Pretitle{}
$Title{Turner Syndrome}
$Subject{Turner Syndrome Bonnevie-Ulrich syndrome Ovarian Dwarfism Ovary
Dysgenesis Ovary Aplasia Genital Dwarfism Gonadal Dysgenesis (XO) Monosomy X
Morgagni-Turner-Albright Syndrome Pterygolymphangiectasia Schereshevkii-Turner
Syndrome Turner-Varny Syndrome XO syndrome Noonan Syndrome (in males) Pseudo
Turner Syndrome (in males) }
$Volume{}
$Log{}

Copyright (C) 1986, 1987, 1988, 1989, 1991, 1992, 1993 National
Organization for Rare Disorders, Inc.

112:
Turner Syndrome

** IMPORTANT **
It is possible that the main title of the article (Turner Syndrome) is
not the name you expected.  Please check the SYNONYM listing to find the
synonyms, disorder subdivisions, and related disorders covered by this
article.

Synonyms

     Bonnevie-Ulrich syndrome
     Ovarian Dwarfism
     Ovary Dysgenesis
     Ovary Aplasia
     Genital Dwarfism
     Gonadal Dysgenesis (XO)
     Monosomy X
     Morgagni-Turner-Albright Syndrome
     Pterygolymphangiectasia
     Schereshevkii-Turner Syndrome
     Turner-Varny Syndrome
     XO syndrome

Information on the following disorders can be found in the Related
Disorders section of this report:

     Noonan Syndrome (in males)
     Pseudo Turner Syndrome (in males)

General Discussion

** REMINDER **
The information contained in the Rare Disease Database is provided for
educational purposes only.  It should not be used for diagnostic or treatment
purposes.  If you wish to obtain more information about this disorder, please
contact your personal physician and/or the agencies listed in the "Resources"
section.


Turner syndrome is a genetic disorder affecting females which is
characterized by lack of sexual development, small stature, possible mental
retardation, a webbed neck, heart defects, and various other congenital
abnormalities.  Individuals have an XO karyotype, i.e., they have neither the
second X chromosome that characterizes females nor the Y chromosome of males.
Despite the unusual genetic karyotype, people with Turner Syndrome are
females.

Symptoms

Individuals with Turner syndrome have female characteristics, but they do not
develop secondary sexual characteristics because they have immature or
"streak" ovaries and cannot produce estrogen (a female hormone).  No puberty
occurs, and sexual traits such as breasts or pubic and axillary hair fail to
develop.

Growth is slowed and the individual remains unusually short, often under
5 feet tall at adulthood.  Intelligence is only rarely impaired.  There may
be behavioral difficulties, but it is not known whether these are
consequences of living with this disorder or neurological manifestations.

Congenital abnormalities of the skeleton, heart, and urinary tract can
occur.  The neck is webbed and the chest may be broad or protruding.  The jaw
may have an unusual shape, and the palate may be arched.  Typical heart
defects may include coarctation of the aorta and other anomalies of the left
side of the heart.  Urinary tract abnormalities may include a horseshoe
shaped kidney and double ureters.

Cells of individuals with Turner syndrome usually have only 45
chromosomes (rather than the normal 46), lacking a sex chromosome as
described above.  Occasionally, the defect is found only in one cell line
(mosaicism), or the chromosome is present but defective.

Causes

Turner Syndrome is a genetic disorder caused by an absence or defect of the
sex chromosome.  Karyotype (chromosomal constitution of the nucleus of a
cell) is XO in 80% of the cases, lacking one of the sex chromosomes.  In 20%
of the cases, sex chromatin is positive for various chromosomal abnormalities
such as XX (one chromosome is abnormal) or XO (one chromosome is absent), or
other abnormal chromosome combinations.

Affected Population

Turner Syndrome affects only females.  In the United States, the number of
persons with this disorder is approximately 45,000.

Related Disorders

Noonan Syndrome is a genetic disorder that can affect both males and females.
The disorder is characterized by a lack of sexual development, short stature,
mental retardation, a webbed neck, skeletal and/or heart defects, and various
other abnormalities.  Persons with Noonan Syndrome usually have normal
chromosomes (karyotype is normal), while their physical appearance
(phenotype) is different from their peers.  (For more information on this
disorder, choose, "Noonan" as your search term in the Rare Disease Database.)

Therapies:  Standard

There is no cure for Turner Syndrome, but certain measures can allow a more
normal life in affected persons.  To increase stature (i.e., for normal
linear growth and maturation of the bones), estradiol therapy started early
in life has been found useful.  Genetically engineered growth hormone has
proven helpful in many cases.  At puberty, replacement therapy with estrogen
may begin.  This allows almost normal development of breasts, labia, vagina,
uterus and fallopian tubes, although patients remain unable to conceive
children.

Patients who are mosaics (i.e., only some of whose cells have abnormal
sex chromosomes) appear to be susceptible to gonadal tumors.  Such patients,
who are likely to have evidence of virilization, may have "streak gonads"
which are undeveloped gonads in the ligaments of the abdominal cavity.  These
should be removed.

Therapies:  Investigational

The National Institutes of Health requests the cooperation of physicians in
referring patients with Turner Syndrome, age 4 to 12 years.  Patients will be
offered enrollment in a long-term treatment protocol to assess the effect of
low-dose estrogen treatment and growth hormone treatment on adult height.
Low-dose estrogen is intended to help stimulate gradual development of
secondary sexual characteristics without compromising growth potential
Referring physicians will receive a complete summary of all evaluations, and
patients will continue to be followed in conjunction with their referring
physicians.  Please write or telephone:

     Dr. Gordon B. Cutler Jr.
     National Institutes of Health
     9000 Rockville Pike
     Bldg. 10, Rm. 10N260
     Bethesda, MD  20892
     [phone]

     or

     Dr. Judith Levine Ross
     Hahnemann University
     Mail Stop 402
     Broad & Vine Streets
     Philadelphia, PA  19102
     [phone]

Ethinyl Estradiol product EE which is manufactured by Gynex increases
secondary sexual characteristics in Turner's patients without causing bone
growth problems.  Further studies are necessary to determine the long-term
safety and effectiveness of this product.

Oxandrolone (Oxandrin) is an experimental drug being tested on girls with
Turner Syndrome to increase their growth.  This drug has several advantages
over human growth hormone (hGH) because (1) Oxandrin is an oral drug whereas
hGH is an injection (2) hGH costs $10,000 to $30,000 per year whereas Oxadrin
is expected to cost less than $2,000 per year.  Oxandrin is available from
Gynex Pharmaceuticals under a "Treatment IND" which is special permission
from the FDA to distribute an investigational drug to a large number of
people who are not in a clinical trial.

This disease entry is based upon medical information available through
February 1993.  Since NORD's resources are limited, it is not possible to
keep every entry in the Rare Disease Database completely current and
accurate.  Please check with the agencies listed in the Resources section for
the most current information about this disorder.

Resources

For more information on Turner Syndrome, please contact:

     National Organization for Rare Disorders (NORD)
     P.O. Box 8923
     New Fairfield, CT  06812-1783
     [phone]

     Turner's Syndrome Support Group of New England
     170 Maple Street
     Malden, MA 02148

     Turner's Syndrome Society of the United States
     3539 Tonkawood Road
     Minnetonka, MN  55345
     [phone]

     Turner Syndrome Society
     Administrative Studies Bldg. 006
     4700 Keel Street
     York University
     Downsview, Ontario, Canada
     M3J 1P3 .BR; [phone]

     NIH/National Institute of Child Health and Human Development
     9000 Rockville Pike
     Bethesda, MD  20892
     [phone]

For genetic information and genetic counseling referrals, please contact:

     March of Dimes Birth Defects Foundation
     1275 Mamaroneck Avenue
     White Plains, NY  10605
     [phone]

     Alliance of Genetic Support Groups
     35 Wisconsin Circle, Suite 440
     Chevy Chase, MD  20815
     (800) 336-GENE
     [phone]

References

CECIL TEXTBOOK OF MEDICINE, 18th ed.:  James B. Wyngaarden, and Lloyd H.
Smith, Jr., Eds.:  W. B. Saunders Co., 1988.  Pp. 167-70, 1392.

SMITH'S RECOGNIZABLE PATTERS OF HUMAN MALFORMATION, 4th ed., Kenneth L.
Jones, M.D., W.B. Saunders, Co. 1988.  Pp. 75-9.