CD-ROM Today 1996 January/CD-ROM Today 1996 January.iso/dp/0387/03875.txt

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$Unique_ID{BRK03875}
$Pretitle{}
$Title{Ichthyosis, Tay Syndrome}
$Subject{Ichthyosis, Tay Syndrome Disorder of Cornification 14
(Trichothiodystrophy Type) DOC 14 (Trichothiodystrophy Type) IBIDS Syndrome
Ichthyosiform Erythroderma with Hair Abnormality and Growth and Mental
Retardation Ichthyosis, Congenital, with Trichothiodystrophy
Trichothiodystrophy with Congenital Ichthyosis BIDS Syndrome (Brittle hair,
Intellectual impairment, Decreased fertility, Short stature;  Amish Brittle
Hair Syndrome) Pollitt Syndrome (Trichorrhexis Nodosa Syndrome) Ichthyoses
(Disorders of Cornification) Netherton Syndrome }
$Volume{}
$Log{}

Copyright (C) 1988, 1989, 1993 National Organization for Rare Disorders,
Inc.

554:
Ichthyosis, Tay Syndrome

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

Synonyms

     Disorder of Cornification 14 (Trichothiodystrophy Type)
     DOC 14 (Trichothiodystrophy Type)
     IBIDS Syndrome
     Ichthyosiform Erythroderma with Hair Abnormality and Growth and Mental
Retardation
     Ichthyosis, Congenital, with Trichothiodystrophy
     Trichothiodystrophy with Congenital Ichthyosis

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

     BIDS Syndrome (Brittle hair, Intellectual impairment, Decreased
fertility, Short stature;  Amish Brittle Hair Syndrome)
     Pollitt Syndrome (Trichorrhexis Nodosa Syndrome)
     Ichthyoses (Disorders of Cornification)
     Netherton 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 physician and/or the agencies listed in the "Resources" section
of this report.


Tay Syndrome is a hereditary disorder characterized by brittle, twisted
hair, scaly dry skin (ichthyosis), and abnormal finger and toe nails.  Loss
of subcutaneous fat results in a prematurely aged-looking face.  Physical
development is usually slowed and mental retardation may also be present.  A
wide variety of central nervous system abnormalities may include seizures,
tremors, lack of muscle coordination (ataxia), and neurosensory deafness.
The reproductive organs are usually underdeveloped.  Very small cataracts
often develop in the eyes.  Abnormalities of the bones and teeth may also
occur, as well as an increased susceptibility to infection.

Symptoms

Tay Syndrome is characterized by brittle, twisted hair that is low in sulfur
content (trichothyodystrophy).  The skin over most of the body surface is
covered with fine, dark scales (ichthyosis).  This so-called "disorder of
cornification" of the skin may be present at birth as a parchment-like
(collodion) membrane.  The sulfur deficient nails are abnormally short,
broad, and ridged, and they split easily.  Loss of subcutaneous fat usually
results in a prematurely old-looking face.  A beaked nose, receding chin, and
protruding ears are also characteristic of Tay Syndrome.

The central nervous system may be affected with seizures, tremors, lack
of muscle coordination, and nerve deafness.  The testes may fail to descend
(cryptorchidism) in males, and female genitalia may be underdeveloped.  In
women, breast tissue may be completely absent in spite of normal development
of the nipples.  Very small cataracts often occur in the eyes.  Bone and
teeth abnormalities appear in some cases.  Patients with Tay Syndrome may
also have an increased susceptibility to infection.

Causes

Tay Syndrome is a hereditary disorder transmitted through autosomal recessive
genes.  (Human traits including the classic genetic diseases, are the product
of the interaction of two genes for that condition, one received from the
father and one from the mother.  In recessive disorders, the condition does
not appear unless a person inherits the same defective gene 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

Tay Syndrome is usually present at birth.  Males and females are affected in
equal numbers.

Related Disorders

Symptoms of the following disorders may resemble those of Tay Syndrome.
Comparisons may be useful for a differential diagnosis:

Amish Brittle Hair Syndrome (Hair-Brain Syndrome; BIDS Syndrome) is a
rare hereditary disorder that tends to occur in people of Amish descent.  It
is characterized by brittle hair, intellectual impairment, decreased
fertility, and short stature.  It lacks the skin and facial abnormalities of
Tay Syndrome.

Pollitt Syndrome (Trichorrhexis Nodosa Syndrome) is a hereditary
disorder characterized by mental and physical retardation, an abnormally
small head and fragile hair (trichorrhexis nodosa) that may fall out.  The
skin is usually scaly and the nails are underdeveloped and spoon-shaped.
Some researchers believe this disorder may be the same as Amish Brittle Hair
Syndrome.

"Ichthyoses" or "Disorders of Cornification" are general terms describing
a group of scaly skin disorders.  They are characterized by an abnormal
accumulation of large amounts of dead skin cells (squames) in the top layer
of the skin.  The conversion of an abnormally large number of epidermal cells
into squamous cells is thought to be caused by a defect in the metabolism of
skin cells known as "corneocytes" or of the fat-rich matrix around these
cells.  The cells can be thought of as bricks, while the matrix would be the
mortar holding these cells together.  (For more information, choose
"Ichthyosis"  as your search term in the Rare Disease Database.)

Netherton Syndrome is a very rare form of ichthyosis that occurs almost
exclusively in females.  It is characterized by scaling of the skin in a
circular pattern.  Hair shafts are held back in the hair root (trichorrhexis
invaginata).  Fragile hair on the head characteristic of this disorder is
called "bamboo hair" (trichorrhexis nodosa).  Patients with Netherton
Syndrome are usually predisposed to allergies such as asthma, or food
allergies which can cause skin eruptions.  (For more information, choose
"Netherton Syndrome" as your search term in the Rare Disease Database.)

Other forms of Ichthyosis include Sjogren-Larsson Syndrome, Ichthyosis
Hystrix, Lamellar Ichthyosis, Refsum Syndrome, Darier Disease, Conradi-
Hunermann Syndrome, Chanarin-Dorfman Syndrome, and Epidermolytic
Hyperkeratosis.  (Choose the appropriate name as your search term for more
information on that disorder in the Rare Disease Database.

Therapies:  Standard

Skin symptoms of Tay Syndrome are treated by applying skin softening
(emollient) ointments, preferably plain petroleum jelly.  This can be
especially effective after bathing while the skin is still moist.  Salicylic
acid gel is another particularly effective ointment.  The skin should be
covered at night with an airtight, waterproof dressing when this ointment is
used.  Lactate lotion can also be an effective treatment for this disorder.

Drugs derived from Vitamin A (retinoids) such as tretinoin, motretinide,
and etretinate can be effective against skin symptoms of Tay Syndrome, but
can cause toxic effects on the bones in some cases.  A synthetic derivative
of Vitamin A, isotretinoin (accutane), when taken by pregnant women, can
cause severe birth defects to the fetus.  These Vitamin A compounds have not
yet been approved by the Food and Drug Administration (FDA) for treatment of
Ichthyosis.

Other treatment is symptomatic and supportive.  Genetic counseling may be
helpful for families of children with Tay Syndrome, and special education
services may be required in school.

Therapies:  Investigational

The National Institute of Arthritis, Musculoskeletal and Skin Diseases is
looking for patients with various kinds of Ichthyosis willing to participate
in research aimed at mapping the genes responsible for their disorder.
Interested persons may contact:

     Dr. Sherri Bale
     National Institute of Arthritis, Musculoskeletal and Skin Diseases
     9000 Rockville Pike
     Bethesda, MD  20892
     [phone]

The orphan product Monolaurin (Glylorin) is being tested for treatment of
Tay Syndrome.  The product is manufactured by:

     Cellegy Pharmaceuticals
     371 Bel Marin Keys, Suite 210
     Novato, CA  94949

This disease entry is based upon medical information available through
May 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 Tay Syndrome, please contact:

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

     Foundation for Ichthyosis and Related Skin Types, Inc. (F.I.R.S.T.)
     P.O. Box 20921
     Raleigh, NC  27619-0921
     [phone]
     [phone]

     The National Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
Information Clearinghouse
     Box AMS
     Bethesda, MD  20892
     [phone]

     International Tremor Foundation
     360 W. Superior St.
     Chicago, IL  60610
     [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

GENETICALLY TRANSMITTED, GENERALIZED DISORDERS OF CORNIFICATION.  THE
ICHTHYOSES:  M.L. Williams, et al.; Dermatol Clin (January 1987:  issue 5(1)).
Pp. 155-178.

THE TAY SYNDROME (CONGENITAL ICHTHYOSIS WITH TRICHOTHIODYSTROPHY):  R.
Happle, et al.; Eur Journal Pediatr (January 1984:  issue 141(3)).  Pp. 147-
152.

THE METABOLIC BASIS OF INHERITED DISEASE, 5th ed.:  John B. Stanbury, et
al., eds.; McGraw Hill, 1983.  Pp. 1027-1039.

MENDELIAN INHERITANCE IN MAN, 7th ed.:  Victor A. McKusick;  Johns
Hopkins University Press, 1986.  Pp. 1058, 1285.