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Usher Syndrome Type I
by Yael Rosenberg, RN
Description
Usher syndrome type I is an autosomal recessive genetic disorder
that is the result of mutations in several genes in different
chromosomal loci. Type 1 is divided into seven distinct subtypes
designated as 1A-1G (1F is the one prevalent in Ashkenazi Jews - A
mutation in the PCDH15 gene, located on chromosome 10).
NIDCD (National Institute on Deafness and Communication Disorders)
researchers, collaborating with researchers from universities in New
York and Israel, pinpointed a mutation of the PCDH15 gene, called
R245X that accounts for a large percentage of type 1 Usher syndrome
in todays Ashkenazi Jewish population.
The genes involved in Usher syndrome are responsible for instruction
to make proteins that play important roles in normal hearing,
balance and vision.
Symptoms
Complete deafness at birth or almost complete hearing loss by age
one.
Decreased night vision before age 10
Tunnel vision by age 16
Progressive vision loss during childhood caused by retinitis
pigmentosa
Poor balance leading children to be slow to sit without support
and inability to walk independently before 18 months.
Incidence and Carriers
Disease frequency: Estimated at 1 in 25,000 for all subtypes of
Usher Syndrome Type I.
11% -19% have type 1F.
1 in 80,000 in Ashkenazi
Jews for Type 1F
Carrier frequency: 1 in 40 to 1 in 100 for specific mutation (R245X)
of the PCDH15 gene
unique to Ashkenazi Jews.
1 in 70 in general
population carries some form of Usher syndrome
Treatment
Currently there is no cure or effective treatment for Usher Syndrome
Type 1
Evaluation for severity of condition includes: Auditory, Vestibular
function and Visual.
Treatment is symptomatic and supportive and includes:
Auditory:
Cochlear implants as hearing aids are frequently ineffectual
Vestibular:
Use of supervised sports may assist the individual affected with
this condition to become more proficient in utilizing somatosensory
factor of the balance
Visual:
There is some evidence that certain preventative measure can
lengthen the time the individual has usable vision:
Sunglasses to protect the retina from UV light
Exercise and diet rich in Omega 3.
Individuals should be taught tactile signing
Currently there are a number of research studies being carried out:
Transplantation of retinal cells
Gene Therapy
Testing
Diagnosis is based on:
Clinical manifestation of profound bilateral sensorineural hearing
loss, retinitis pigmentosa and poor balance.
Family history
Genetic testing for a specific mutation (R245X mutation of the
PCDH15 gene by Ashkenazi Jews)
Laboratories and Screening
The following laboratories offer genetic testing for
Usher Syndrome Type 1F:
United States
Israel
UNITED STATES
Genzyme Genetics
Molecular Diagnostic Laboratory
3400 Computer Drive
Westborough, MA 01581
Phone: (508) 898-9001
Fax: (508) 389-5549
Toll Free: (800) 255-7357
Genzyme Genetics General Inquiries:
Phone: (800) 357-5744
Fax: (508) 389-5549
Client Services - Reproductive Genetics
Toll Free: (800) 848-4436
Harvard Medical School and Partners Healthcare
Laboratory for Molecular Medicine
Cambridge, MA
Phone: (617) 768-8500
Email: LMM@partners.org
John and Marcia Carver
Nonprofit Genetic Testing Laboratory
375 Newton Rd.
4111 MERF
Iowa City, IA 52242
Email: carverlab@uiowa.edu
Fax: (319) 355-7142
Mount Sinai Genetic Testing Laboratory (DNA Division)
The Mount Sinai Medical Center
One Gustave L. Levy Place
New York, NY 10029-6574
Phone: (212) 241-3055
Fax: (212) 241-9467
Email: rochelle.pakier@mssm.edu
PreventionGenetics
Molecular Diagnostics and BioBanking
3700 Downwind Drive
Marshfield, Wisconsin 54449 USA
Phone: (715) 387-0484
Fax: (715) 384-3661
Web:
http://www.preventiongenetics.com
ISRAEL
Carmel Medical Center
Molecular Genetics Laboratory
Michal Street
Haifa 34362 Israel
Phone: (+972) 4-8250407
Hadassah Hospital Hadassah Ein Karem
Human Molecular Genetic Laboratory
Dr. Israela (Issy) Lerer (Director)
POB 12000
Jerusalem 91120 Israel
Phone: (+972) 2- 677-6016
Fax : (+972) 2- 677-7499
Web: http://www.hadassah.org.il
HaEmek Medical Center
Molecular Genetics Unit
Afula 18101 , Israel
Phone: (+972) 4-649-5416
Email:
morad_kh@clalit.org.il
Kaplan medical center, Molecular Genetics Laboratory
REHOVOT , ISRAEL
Phone: (+972) 8-944-1534
Web:
http://www.clalit.org.il/kaplan
Meir Medical Center
Molecular Genetics Laboratory
Kfar Saba , Israel
Phone: (+972) 9-747-1059
Web:
http://www.clalit.org.il/meir/Content/Content.asp
Meuhedet Rosh Haayin
Molecular Genetics Laboratory.
Hey Beiyar 22 Rosh Haayin 48056 Israel
Phone: (+972) 3-915-5330
Fax: (+972) 3-915-5331
Web: https://www.meuhedet.co.il
Pronto Diagnostic Ltd.
19A Habarzel Street
Ramat Hachayal
Tel Aviv 69710, Israel
Phone: (+972) 73-312-6155
Fax: (+972) 73-212-6144
Email:
info@prontodiagnostics.com
Rabin Medical Center
Molecular Genetics
Petah Tikva, Israel
Director: Mordechai Shohat, MD
Genetic Counselor: Inbal Kedar, MSc
Phone: (+972) 3-937-7659
Fax: (+972) 3-937-7660
Email: inbalkd@clalit.org.il
Rambam Medical Center
Molecular Genetics Laboratory
PO Box 9602 Haifa 31096 Israel
Phone: (+972)- 4-8542456
Sheba Medical Center
The Danek Gertner Institute Human Genetics
Molecular diagnosis Laboratory
Tel Hashomer
Ramat Gan 52621, Israel
Phone: (+972) 3-530-3060
Web: http://www.eng.sheba.co.il
Soroka University Medical Center
Genetics Laboratories
Beer-Sheva , Israel
Phone: (+972) 8-6400258
Web:
http://www.clalit.org.il/soroka/Content/Content.asp?CID=43&u=420
Tel Aviv Sourasky Medical Center
Genetic Lab
Sourasky Builidng, 1st Floor, Wing 1
Tel Aviv, Israel
Phone: (+972) 3-697-4704
Phone: (+972) 3-697-3992
Fax: (+972) 3-697-4555
Web: http://www.tasmc.org.il
Western Galilee Hospital-Naharia
Molecular Genetics Laboratory
P.O.Box 21
Naharia 2100 Israel
Resources and More
Foundation Fighting Blindness
7168 Columbia Gateway Drive, Suite 100
Columbia, MD 21046
Toll Free: (800) 683-5555
TDD: (800) 683-5551
Phone: (410) 423-0600
Local TDD: (410) 363-7139
Email:
info@FightBlindness.org
Alexander Graham Bell Association for the Deaf and Hard of Hearing
3417 Volta Place Northwest
Washington DC 20007
Toll Free: (866) 337-5220
Phone: (202) 337-5220
TTY: (202) 337-5221
Fax: (202) 337-8314
Email: info@agbell.org
Web: http://www.agbell.org
American Society for Deaf Children (ASDC)
800 Florida Avenue Northeast #2047
Washington DC 20002-3695
Toll Free: (800) 942-2732 ( Parent Hotline)
Toll Free: (866) 895-4206 (voice/TTY)
Fax: (410) 795-0965
Email: info@deafchildren.org
Email: asdc@deafchildren.org
Web:
http://www.deafchildren.org
Boys Town National Research Hospital
555 North 30th Street
Omaha, NE 68131
Phone: (402) 498-6511
Web:
http://www.boystownhospital.org
My baby's hearing
This site, developed with support from the National Institute on
Deafness and Other Communication Disorders, provides information
about newborn hearing screening and hearing loss.
Web: http://www.babyhearing.org
National Association of the Deaf (NAD)
8630 Fenton Street
Suite 820
Silver Spring MD 20910
Phone: (301) 587-1788;
TTY: (301) 587-1789
Fax: (301) 587-1791
Email: nad.info@nad.org
Web: http://www.nad.org
SENSE
101 Pentonville Road
London N1 9LG
United Kingdom
Phone: (+44) 845 127 0060 (voice)
Textphone: (+44) 0845 127 0062
Fax: (+44) 845 127 0061
Email: info@sense.org.uk
Web: http://www.sense.org
Support Groups
Usher Family Support
11435 Cronhill Drive
Owings Mills, MD 21117
Toll Free: (800) 683-5555
Web:
http://www.blindness.org/usher
Usher- Friends
Web:
http://groups.yahoo.com/group/Usher-Friends
Ushers
Web:http://health.groups.yahoo.com/group/Ushers/?v=1&t=search&ch=web&pub=groups&sec=group&slk=2
Usherlife
Web:http://groups.yahoo.com/group/usherlife/?v=1&t=search&ch=web&pub=groups&sec=group&slk=4
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