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$Unique_ID{BRK03400}
$Pretitle{}
$Title{11q Syndrome}
$Subject{11q Syndrome Jacobsen Syndrome Deletion on Long Arm of Chromosome 11
Deletion on Short Arm of Chromosome 11 Partial Trisomy of 11q Trisomy 8
Partial Trisomy 6p Trisomy 9p Trisomy 10q Trisomy 13 (Patau's Syndrome)
Trisomy 18 (Edward's Syndrome) Trisomy 21 (Down Syndrome) Trisomy 22 (Cat-Eye
Syndrome)}
$Volume{}
$Log{}

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

641:
11q Syndrome

** IMPORTANT **
It is possible that the main title of the article (11q 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

     Jacobsen Syndrome
     Deletion on Long Arm of Chromosome 11

Disorder Subdivisions:

     Deletion on Short Arm of Chromosome 11
     Partial Trisomy of 11q

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

     Trisomy 8
     Partial Trisomy 6p
     Trisomy 9p
     Trisomy 10q
     Trisomy 13 (Patau's Syndrome)
     Trisomy 18 (Edward's Syndrome)
     Trisomy 21 (Down Syndrome)
     Trisomy 22 (Cat-Eye 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.

11q Syndrome (Jacobsen Syndrome) is a rare genetic disorder affecting the
long arm of chromosome 11.  The disorder may be characterized by a narrow
protruding forehead, eye problems, abnormally shaped nose and mouth, and
mental retardation.

Symptoms

Symptoms of 11q Syndrome include very widely spaced eyes (hypertelorism),
drooping eyelids (ptosis), abnormally turned eyes (strabismus) and abnormal
positioning of the eyes.  Symptoms may also include a narrow protruding
forehead, broad nasal root, short upturned tip of the nose, a carp shaped
(fish-like) mouth, receding chin, misshapen ears, simian creases in the hands
and mental retardation.

Causes

11q Syndrome is caused by a deletion on the long arm (q) of chromosome 11.
The severity and type of abnormality depends upon the size and location of
the missing chromosome piece.  The cause of the chromosome break itself is
unknown.  Chromosomes are found in the nucleus of all body cells.  They carry
the genetic characteristics of each individual.  Pairs of human chromosomes
are numbered from 1 through 22, with an unequal 23rd pair of X and Y
chromosomes for males, and two X chromosomes for females.  Many birth defects
are classified by the name of the abnormal chromosome pair and which portion
of the chromosome is affected.  For example, 11q- means that there is a
deletion on the long arm of the chromosome 11 pair.  If the letter p is shown
next to the number of the chromosome pair it means that the defect is on the
short arm of the chromosome.  There can also be a defect called trisomy which
means that there is an extra chromosome added to the chromosome pair.

Affected Population

11q is a rare genetic disorder which is present at birth and seems to affect
males and females in equal numbers.

Related Disorders

Symptoms of the following disorders can be similar to those of 11q.
Comparisons may be useful for a differential diagnosis:

Trisomy 8 patients are often slender and of normal height.  The ears are
low-set and malformed, and the eyes tend to be slanted down.  Bone and joint
abnormalities may involve the ribs, spine and kneecaps; joint contractures
with poor range of motion are frequent.  Unusually deep creases in the palms
of the hands and the soles of the feet are evident.  There is mild to
moderate mental and motor retardation, often with delayed and hard to
understand speech.  Most of the patients are chromosomal mosaics, (i.e., they
have two or more cell types that have different numbers of chromosomes).

Partial Trisomy 6p is characterized by a triplication of a section of the
short arm of the 6th Chromosome.  Mental retardation, multiple facial
abnormalities as well as malformations of the lungs and kidneys and the
presence of two kidneys on one side of the body with crossed ureters may
occur.

Trisomy 9p is identified by an extra short arm of the 9th chromosome.
This disorder is characterized by abnormalities in the hands, feet, and
pelvic bones.  The pattern of bone structures in X-rays of patients with
Trisomy 9P appears to be unique among patients with chromosomal
abnormalities.  Other symptoms include down-turned corners of the mouth, a
large rounded nose, slightly wide and deep-set slanted eyes, unusual
fingerprints and mental retardation.

Trisomy 10q is characterized by a triplication of part of the long arm of
the 10th chromosome.  The predominant symptoms of this disorder include a
long head (dolichocephaly), prominent forehead, and the skull shows
abnormally open seams and soft spots (fontanelles) at birth.  A broad nose,
cleft lip and palate, clubfoot, and cysts in the kidneys may also occur.

Trisomy 13 Syndrome (Patau's Syndrome) is a genetic disorder which occurs
in approximately 1 in 5,000 live births.  It is characterized by midline
abnormalities, gross defects of the brain, mental retardation, and cleft lip
and/or cleft plate.  (For more information on this disorder, choose "Trisomy
13" as your search term in the Rare Disease Database).

Trisomy 18 Syndrome (Edwards' Syndrome) is a rare genetic disorder.
Paternal and maternal ages are usually higher than average.  The babies
appear thin and frail.  They fail to thrive and have difficulty feeding.
These children show generalized increased muscle tension (hypertonicity) with
rigidity in flexion of the limbs, and mental retardation.  (For more
information on this disorder, choose "Trisomy 18" as your search term in the
Rare Disease Database).

Partial Trisomy 22 (Cat-Eye Syndrome) is characterized by a congenital
absence or defect of certain eye tissue called coloboma, and the lack of an
opening for the anus (atresia).  Severe mental and physical retardation,
wideset slanted eyes, small skin appendages (tags) or openings to the inside
of the mouth (fistulas) in front of the ears may develop.  Congenital heart
disease may also occur.  Full trisomy has been reported in a few patients
with similar symptoms, but a small jaw and low muscle tone (hypotonia)
distinguishes them from the partial Trisomy.

Trisomy 21, also known as Down Syndrome is the most prevalent and readily
identifiable genetic condition associated with mental retardation.  The extra
chromosome 21 changes the orderly development of body and brain.  (For more
information on this disorder, choose "Down" as your search term in the Rare
Disease Database).

The following disorders may be associated with 11q as secondary
characteristics.  They are not necessary for a differential diagnosis:

Mosaicism is a disorder in which just some cells of the body have partial
chromosome deletions and the other cells are normal.  The abnormalities of
Mosaics have greater variability of type and severity due to the presence of
normal cells.

Monosomy may refer to any deletion of the chromosome.  Part or all of the
short arm (p) and/or the long arm(q) of the chromosome may be missing.  Since
chromosomes occur in pairs, Monosomy could also refer to the absence of one
of the pair.

Trisomy is characterized by an additional chromosome.

Intrachromosomal Insertion involves the breaking off of a section of a
chromosome and its subsequent reattachment in a different way (inversion).

Ring Chromosome is characterized by the chromosome being shaped in a ring
or O shape.

Other deletions on the long arm (q) of chromosome 11 may be associated
with iron overload in myelodysplastic (spinal cord) syndromes as well as a
smaller than normal sized head (craniosynostosis) and webbed fingers and toes
(syndactyly).  11q 22 or 23 may also be associated with anal canal carcinoma
(cancer) and myeloid leukemia (blood cancer).

Deletion on the short arm of 11p 13 may be the cause of Wilms Tumor.
Wilms Tumor is the most common form of kidney cancer in children, accounting
for six to eight percent of all childhood cancers.  Abdominal swelling is the
most common symptom usually leading to early detection of the disease.  Later
signs may include blood in the urine, low-grade fever, loss of appetite,
paleness, weight loss, and lethargy.  Wilms' Tumor can often be treated
successfully depending on the stage of the tumor at detection and the age and
general health of the child.  Approximately eighty percent of children with
this disease can be cured with appropriate treatment.  (For more information
on this disorder, choose "Wilms" as your search term in the Rate Disease
Database).

Partial Trisomy 11q may include severe psychomotor retardation, a smaller
than normal sized head (microcephaly), cleft palate, large beaked nose, a
smaller than normal sized jaw (micrognathia), short hands and displaced
thumbs.

Therapies:  Standard

Special education, physical therapy, and vocational services may be of
benefit for the 11q patient.  Genetic counseling will be of benefit for
affected families.  Other treatment is symptomatic and supportive.

Therapies:  Investigational

This disease entry is based upon medical information available through April
1989.  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 11q Syndrome, please contact:

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

     Support Organization for Trisomy (S.O.F.T) and Other Related Disorders
     9349 S. 12th Street
     Schoolcraft, MI 49087

     Chromosome Deletion Outreach
     P.O. Box 164
     Holtsville, NY  11742
     [phone]

     National Institute of Child Health and Human Development (NICHHD)
     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

PARTIAL DELETION OF LONG ARM OF CHROMOSOME 11 [del (11) (q 23)]:  JACOBSEN
SYNDROME.  TWO NEW CASES AND REVIEW OF THE CLINICAL FINDINGS.  A. Schinzel et
al.; J Med Genet (December, 1977, issue 14 (6)).  Pp. 438-444.

GENETIC MECHANISMS OF TUMOR-SPECIFIC LOSS OF 11p DNA SEQUENCES IN WILMS
TUMOR.  D. D. Dao, et al.; Am J Hum Genet (August, 1987, issue 41 (2)).  Pp.
202-217.

RECURRENT DELETIONS OF CHROMOSOMES 11q AND 3p IN ANAL CANAL CARCINOMA.
M. Muleris, et al.; Int J Cancer (May 15, 1987, issue 39 (5)).  Pp. 595-598.

A PATIENT WITH PARTIAL DUPLICATION 2q AND PARTIAL DEFICIENCY 11q.  C.K.
Ho, et al.; Am J Med Genet (November, 1987, issue 28 (3)).  Pp. 575-579.

INTERSTITIAL DELETION OF THE LONG ARM OF CHROMOSOME 11.  A. Carneval, et
al.; Ann Genet (1987, issue 30 (1)).  Pp. 56-58.