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$Unique_ID{BRK04323}
$Pretitle{}
$Title{Weaver Syndrome}
$Subject{Weaver Syndrome Weaver-Smith Syndrome WSS Marshall-Smith Syndrome
Gigantism Sotos Syndrome McCune-Albright Syndrome }
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Copyright (C) 1990 National Organization for Rare Disorders, Inc.

817:
Weaver Syndrome

** IMPORTANT **
It is possible that the main title of the article (Weaver Syndrome) is
not the name you expected.  Please check the SYNONYM listing to find the
alternate names and disorder subdivisions covered by this article.

Synonyms

     Weaver-Smith Syndrome
     WSS

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

     Marshall-Smith Syndrome
     Gigantism
     Sotos Syndrome
     McCune-Albright Syndrome

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 of this report.

Weaver Syndrome is characterized by rapid growth.  Usually starting
before birth (prenatal onset), physical growth and bone development
(maturation) can occur more quickly than average.  Other symptoms can include
increased muscle tone (hypertonia) with exaggerated reflexes (spasticity),
slow development of voluntary movements (psychomotor retardation), specific
physical characteristics, and/or foot deformities.  Babies with this syndrome
have a hoarse low-pitched cry.

Symptoms

In patients with Weaver Syndrome growth and bone development (maturation)
occur faster than normal, with normal to above normal weight in relation to
the patient's height.  Some bones may be wider than average.  In a small
number of patients, this faster than normal rate of growth may not occur, or
does not begin until the baby is a few months old.  Hypertonia, increased
muscle tone with exaggerated reflexes (spasticity) which is progressive,
and/or slow development of voluntary movements (psychomotor retardation) may
occur.  Babies with this syndrome have a hoarse low-pitched cry.

Individuals with Weaver Syndrome may have extremely wide-set eyes
(hypertelorism), sometimes with excess skin over the inner corner of the eyes
(epicanthal folds), or other eyelid abnormalities (downslanting palpebral
fissures).  The back part of the head (occiput) may be flat, the forehead
broad, and the ears unusually large.  The natural groove located above the
upper lip and below the nose (philtrum) may be longer than average.  The jaw
may appear somewhat smaller than normal (micrognathia).  Other physical
characteristics can include thin hair, inverted nipples and skin which
appears somewhat loose.

Thumbs of people with Weaver Syndrome are usually broad.  One or more
fingers may be permanently bent (camptodactyly).  Nails can be deep-set and
thin.  The pads of the fingertips are usually prominent.  Malformed toes
(clinodactyly), an abnormally high arch (pes cavus), a clubfoot with the sole
of the foot turned inward and upward either in the direction of the heel
(talipes equinovarus) or of the toes (talipes calcaneovalgus), or a twisted
foot (metatarsus adductus) may be present.  Individuals may not be able to
extend their elbows or knees out very far.

In some patients, hernias in the abdomen (inguinal or umbilical hernias)
may develop.  Occasionally, one of the long bones in the foot (fourth
metatarsal) is shorter than average.  Brain abnormalities such as enlarged
vessels and too many blood vessels (hypervascularization), atrophy (cerebral
atrophy), or a cyst in a certain area of the brain (septum pellucidum) may
occur in some patients.

Causes

The exact cause of Weaver Syndrome is unknown.  Some researchers think,
because there have been some cases of mildly affected mothers having sons who
are more severely affected, that Weaver Syndrome may be inherited as an
autosomal dominant trait with a gender-limited expression of symptoms, or an
X-linked recessive trait.  Others think that it may be an autosomal recessive
trait.  In some cases there are no signs of heredity in a family and the
cause is unknown.

Human traits, including the classic genetic diseases, are the product of
the interaction of two genes, one received from the father and one from the
mother.

In dominant disorders a single copy of the disease gene (received from
either the mother or father) will be expressed "dominating" the other normal
gene and resulting in appearance of the disease.  The risk of transmitting
the disorder from affected parent to offspring is fifty percent for each
pregnancy regardless of the sex of the resulting child.

X-linked recessive disorders are conditions which are coded on the X
chromosome.  Females have two X chromosomes, but males have one X chromosome
and one Y chromosome.  Therefore, in females, disease traits on the X
chromosome can be masked by the normal gene on the other X chromosome.  Since
males only have one X chromosome, if they inherit a gene for a disease
present on the X, it will be expressed.  Men with X-linked disorders transmit
the gene to all their daughters, who are carriers, but never to their sons.
Women who are carriers of an X-linked disorder have a fifty percent risk of
transmitting the carrier condition to their daughters, and a fifty percent
risk of transmitting the disease to their sons.

In recessive disorders, the condition does not appear unless a person
inherits the same defective gene for the same trait from each parent.  If one
receives one normal gene and one gene for the disease, the person will be a
carrier for the disease, but usually will show no symptoms.  The risk of
transmitting the disease to the children of a couple, both of whom are
carriers for a recessive disorder, is twenty-five percent.  Fifty percent of
their children will be carriers, but healthy as described above.  Twenty-five
percent of their children will receive both normal genes, one from each
parent, and will be genetically normal.

Affected Population

Weaver Syndrome is a rare disorder affecting males three times more often
than females.  The syndrome is usually present before birth (prenatal onset).

Related Disorders

Marshall-Smith Syndrome is similar to Weaver Syndrome in that growth and bone
maturation occur faster than normal.  However, patients with Marshall-Smith
Syndrome are underweight in relation to their height whereas patients with
Weaver Syndrome have normal to above normal weight in relation to their
height.  Marshall-Smith Syndrome patients also have respiratory difficulties,
different physical characteristics and other symptoms that patients with
Weaver Syndrome do not have.  (For more information on this disorder, choose
"Marshall-Smith" as your search term in the Rare Disease Database).

Gigantism occurs before puberty and is caused by oversecretion of growth
hormone.  It is characterized by excessive growth during childhood with
relatively normal body proportions and sexual development.  Height sometimes
reaches 7 or 8 feet.  Soft tissues are also enlarged.  In extreme cases,
disease of muscle tissue (myopathy) and abnormalities of nerves distant from
the brain and spinal cord (peripheral neuropathy) may occur.  Certain
hereditary syndromes such as Klinefelter Syndrome, Marfan Syndrome, Soto's
Syndrome and some of the lipodystrophies, may include unusually tall height
among their symptoms.  (For more information on disorders involving
gigantism, choose "gigantism or "giant"  as your search term in the Rare
Disease Database.  For more information, choose "peripheral neuropathy,"
"Marfan," and "Klinefelter" as your search terms in the Rare Disease
Database).

Soto's Syndrome is a rare, hereditary disorder characterized by excessive
growth (over the 90th percentile) during the first 4 to 5 years of life.
Abnormalities of the nervous system, including aggressiveness, irritability,
clumsiness, an awkward gait, and mental retardation sometimes also occur.
Physical characteristics also include eyes which appear to be abnormally far
apart (hypertelorism) and slanted.  (For more information, choose "Soto" as
your search term in the Rare Disease Database.)

McCune-Albright Syndrome (Osteitis Fibrosa Disseminata) is characterized
by an early (precocious) sexual development, a change in bone integrity which
produces pain, increasing deformity and disability, and possible changes in
skin pigmentation.  This syndrome involves the endocrine, muscle and bone
systems.  Excessive secretion of growth hormone as well as other hormones
occurs in some cases.  Children with McCune-Albright Syndrome are excessively
tall during childhood, but their growth stops early and they usually don't
reach normal height during adulthood.  (For more information, choose "McCune-
Albright Syndrome" as your search term in the Rare Disease Database.)

Therapies:  Standard

Treatment of Weaver Syndrome is symptomatic and supportive.  An orthopedist
can be consulted for correction of foot deformities.  Genetic counseling may
be of benefit to patients and their families.

Therapies:  Investigational

This disease entry is based upon medical information available through
November 1990.  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 Weaver Syndrome, please contact:

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

     The Magic Foundation
     1327 N. Harlem Ave.
     Oak Park, IL  60302
     [phone]

     Human Growth Foundation (HGF)
     7777 Leesburg Pike
     P.O. Box 3090
     Falls Church, VA  22043
     [phone]
     [phone]

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

For genetic information and genetic counseling referrals:

     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

SMITH'S RECOGNIZABLE PATTERNS OF HUMAN MALFORMATION, 4th Ed.:  Kenneth Lyons
Jones, M.D.; W.B. Saunders Co., 1988.  Pp. 130-135.

A GIRL WITH THE WEAVER SYNDROME.  E. M. Thompson; J Med Genet (Apr 1987;
issue 24 (4)).  Pp. 232-234.

A NEW AUTOSOMAL RECESSIVE DISORDER RESEMBLING WEAVER SYNDROME.  A. S.
Teebi, et al.; Am J Med Genet (Aug 1989; issue 33 (4)).  Pp. 479-482.

FURTHER DELINEATION OF WEAVER SYNDROME.  H. H. Ardinger, et al.; J
Pediatr (Feb 1986; issue 108 (2)).  Pp. 228-235.

THE SYNDROMES OF MARSHALL AND WEAVER.  N. Fitch; J Med Genet (Jun 1980;
issue 17 (3)).  Pp. 174-178.

WEAVER-SMITH SYNDROME.  A CASE STUDY WITH LONG-TERM FOLLOW-UP.  N. Amir,
et al.; Am J Dis Child (Dec 1984; issue 138 (12)).  Pp. 1113-1117.

WEAVER SYNDROME:  THE CHANGING PHENOTYPE IN AN ADULT.  F. Greenberg, et
al.; Am J Med Genet (May 1989; issue 33 (1)).  Pp. 127-129.

WEAVER SYNDROME WITH PES CAVUS.  S. A. Farrell and H. E. Hughes; Am J Med
Genet (Aug 1985; issue 21 (4)).  Pp. 737-739.