Juvenile-HD

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JHD Info-Stanford Univ.
Physician's Guide To HD
Caring for People with HD
Physical & Occupational Therapy In HD
Understanding Behaviour in HD-Dr. Jane Paulsen
Understanding Behavioral-Dr. Edmond Chiu
Advanced Stages Caregivers Handbook
First Shift-Certified Nursing Assistants
Activities of Daily Living-HD
Unified HD Rating Scale (UHDRS) Motor Section
Westphal Variant
SECTION 1 - AT RISK
Age & Probability Chart
At Risk For HD-What Next?
At-Risk Checklist
Best Interest of Child?
Crystal Ball?
Food For Thought
Parent Hasn't Tested?
Q&A On Risk of Inheriting JHD
Testing Children
SECTION 2 - GENETIC TESTING
Genetic Disorders & Birth Defects
Genetic Testing for HD
Genetic Counseling-In General
Psychological Impact
Intro: Genetics/Genetic Testing
Prenatal & Preimplanation
Prenatal Testing-In General
o Genetic Testing Resources
o Personal Stories
SECTION 3 - JHD
Coping With The Early Years
Age of HD Appearance
Age of Onset-Historical
Family-HD Underestimated
Children of Parents With HD
Child~Parent Ill
Clinical Description JHD
HD - What Kids Are Saying
HD & Me
JHD-Duration of Illness
JHD-Clinical and Research
JHD Symptoms
Parenting With HD
Patients/Families Coping
Talking With Children About HD
5 Stages of HD
JHD Resources
SECTION 4 - SYMPTOM RECOGNITION
Parent Resources
8 Fears of A Chronic Illness
Anxiety/Apathy/Irritability~HD
Anxiety, Fears & Phobias
Apathy-Physician's Guide
Ataxia
Attention-Perceptual/Unawareness Physician's Guide
Bed/Pressure Sores
Bed/Pressure Ulcer Guideline
Behavior Management
Bi-Polar Disorders
Botulinum toxin therapy
Bradykinesia
Caring Tips
Child Abuse-Reconizing Signs
Chorea-Physician's Guide
Chorea
Cognitive/Decision Making/Impulsivity
Cognitive-Short Tips
Contractures~Joints Locking
Dehydration-Physician's Guide
Dehydration
Delirium
Denial of HD
Depression~Physician's Guide
Depression-Understanding It
Depression-How To Help
Depression - Treatment Resistant Patient
Depression-Other Resources
-Read If Your Child Is On Antidepressant
Disgust - Impaired Recognition in HD
Dissociative disorders
Driving - Physician's Guide
Dyslexia
Dyslexia Resources
Dystonia
Dystonia/Rigidity & Spasticity Physician's Guide
Dystonia-Predominant Adult-Onset HD
Epileptic Seizures and Epilepsy
Epilepsy-Seizures~PG
-Seizures ~Special Populations
Falling~Safety
Falling - Subdural Hematoma Risk
Fevers - Unexplained
Fevers, sweating & menstural cycles in HD
GERD (Stomach)
HD Principle Treatments
Hallucinations/Psychosis~PGHD
Hand muscle reflexes in HD
Hypothalamus - A Personal Theory
Insomia ~Physician's Guide
Irritability~Temper Outburst Physician's Guide
Learning Disability
Mania/OCD~Physician's Guide
Mood Disorder Rate In HD
Myoclonus (Movements)
Nails-What To Look For
Night Terrors
Obsessive Compulsive OCD
Panic Disorder
Personality disorders
Pneumonia
Pneumonia-Advanced Stages
Pneumonia - Aspirated (Inhaled)
Prosody - Social Impairment
Sexuality~Physician's Guide
Skins Sensitivity
Sleep Disorders
Smoking-Physician's Guide
Spasticity
Stress
Tremors
Why Certain Symptoms Occur
Symptom & Treatment Resources
SECTION 5 - COMMUNICATION
Communication Resources
Communication Problems
Communication Strategies For HD~Jeff Searle
SECTION 6 - EATING/SWALLOWING/NUITRITION
Hints For Weight Loss in HD
HD & Diet~HSA Fact Sheet 7
Nutrients: Some Possible Deficiency Symptoms
Nutrition and HD~Anna Gaba (Recipes)
Nutrition Information In HD~Naomi Lundeen
Speech & Swallowing~Lynn Rhodes
Swallowing & Nutrition Physician's Guide To HD
Swallowing & Nuitrition Resources
Swallowing Warning Signs
5 Swallowing Problems
Taste changes in HD
Weight Gain
Resources-Drinks/Shakes
-Feeding Tubes~Advanced Stages of HD
-Feeding Tube~Jean Miller
-Feeding Tubes: One More Word ~Jean Miller
-Feeding Tubes & Baby Foods
-Feeding Tube~Dental Care
-Feeding Tube Instructions~Jean Miller
-Feeding Tube Resources
SECTION 7 - THERAPIES
Finding a Therapist - Behavoir
What Is A Physiotherapist?
Physical Therapy In HD
Speech-Language Therapy
Therapy Descriptions
Therapy Resources- Easter Seal
Therapy Resources
SECTION 8 - MEDICATIONS
HD Treatments
Medications-Movement Disorders
Medication/Emergency Info Forms
Cutting Prescriptions
Drugs-Look 'Em Up
-Adolescents Under 25
-Antidepressant Adverse Effects
-Anti-psychotic
-Anxiety-Antidepressant
A-Z Mental Health Drugs
-Creatine
-EPA~Fish Oil
-Haldol/Haloperidol - Clinical Sheet
-Haldol~Clinician Description
-Haldol & HD
-Haldol/HD Patient Experiences
-Haldol~ Patient Handout
-Mood Stabilizers: ASK 3 Questions
-Neuroleptic Malignant Synd WARNING
-Olanzipine-Risperidone/blood tests
-Celexa/Luvox/Paxil/Prozac/Zoloft
-Psychiatric Drugs & Children
Sertraline ~Zoloft
-Spasticity Meds/Treatments
-SSRI Medications
-Tardive Dyskinesia WARNING
-Weight Gain Medications
-Sites/Help the Medicine Go Down
-Vitamin & Mineral Deficiencies
SECTION 9 - SURGERIES
Surgery-Movement Disorders
o Surgery Resources
SECTION 10 - PROCEDURES
Clinic Visits-How To Prepare
CT Scans, MRI's etc.
Swallowing Tests
Tests Commonly Used
o Procedures Resources
SECTION 11- ALCOHOL/DRUGS
Alcohol-Parent's Guide
Alcohol-Talking To Your Child
Drugs-What To Do?
Drugs-Talking To Your Child
Disciplining-Ages 0-13 & Up
SECTION 12- SUICIDE
Straight Talk On Suicide
Teen Suicide-You Need To Know
o Suicide Resources
SECTION 13 - DIVORCE
Divorce & Child Stress
Tips For Divorcing Parents
SECTION 14 - DISABILITY ISSUES
Guides To Disability Issues
Caring-Child & Medical Technology
Caring for a Seriously Ill Child
Child Long Term Illness
Disability-Special Education Plan
IFSP Early Intervention Process
Disability Resources
Financial Planning
Wishes Can Come True-Children's Wish Foundations
Special Needs Resources
Special Needs Camp - About
Special Needs Camp - Finding One
SECTION 15 - ASSISTIVE TECHNOLOGY
Child Assistive Technology
Adaptive Equipment Resources
Products
SECTION 16 - EMOTIONAL ISSUES
Signs of Unhealthy Self-Esteem
Emotional Behavior Links
o Emotional Support Resources
SECTION 17 - GRIEF
Helping Child Deal With Death
o Grief Addtional Resources
SECTION 18 - ADD/ADHD
ADD & Teens
Conduct Disorders
FAQS & Related Info
Understanding AD/HD
What Is AD/HD?
Research Articles
Resources
SECTION 19 - HD SUPPORT GROUPS
HD Support Groups
National Youth Association
SECTION 20 - HD LINKS
HD Links
Related Resources
Tips For Friends
SECTION 21 - BENEFITS/INSURNACE
HD Disability
Benefits Check UP - See What You Can Get
Medical Insurance Bureau's Facts On You!
Medicare-Medicaid
Medicare Rights-Home Health & Hospice
Medicare Rights Center Resources
No Insurance? Try This!
Prescription Drug Cards Part I
Prescription Drug Cards Part II
Social Security-Children With Disabilities
SECTION 22 - ARTICLES/JHD
JHD and ADD
SECTION 23 - CAREGIVING
Articles-Resources
Caregiver Self-Assessment
Caregiver's Handbook
"First Shift With A Person With HD"
Getting Respite Care/Help At Home
Helpful Forms-Info
Home Emergency Preparations
Symptom Management
Ten Tips
Useful Tools
SECTION 24 - BIO
Our Personal Experience
Coping At The End
Kelly E. Miller
Song & Verse
Letter From My Heart
GUESTBOOK
Intro: Genetics/Genetic Testing

INDEX Page

 
What do you know about your family tree? Have any of your relatives
had health problems that tend to "run in families"? Which of these
problems affected your parents or grandparents? Which ones affect
you now, or your brothers or sisters? Which problems might you pass
on to your children?
 
Thanks to advances in genetics, doctors now have the tools to
understand how certain illnesses, or increased risks for certain illnesses,
pass from generation to generation.
 
According to some health experts, the definition of an inherited or "genetic"
illness should be expanded beyond the classic inherited disorders (like
hemophilia and sickle cell anemia) to include many types of cancer, Alzheimer's
disease, and other illnesses. They look toward a future where genetic test
results are an important part of every healthy person's medical file. Let's
see what this new biotechnology can mean to you and your family.
 
Genes and Chromosomes
 
Each of us has a unique set of chemical "blueprints" that determines
how our body looks and functions. These blueprints are contained in
a complex chemical called DNA, a long, spiral-shaped molecule that is
found inside each body cell.
 
Specific segments of DNA that contain the instructions for making specifi
body proteins are called genes. Right now, scientists believe that human
DNA carries up to 30,000 genes. Some genes direct the formation of
structural proteins that eventually determine how our bodies look (blue
eyes or brown, curly hair or straight), while others code for important
body chemicals called enzymes.
 
Sometimes, depending on what a specific gene codes for, even a small
genetic error can mean serious problems for the entire body. Sometimes,
an error in just one gene can mean the difference between a normal life
and one that is shortened or physically difficult.
 
Genes line up along the length of human DNA, neatly packaged in
structures called chromosomes. Human cells have 46 chromosomes,
arranged in 23 pairs, with one member of each pair inherited from
each parent at the time of conception.
 
After conception, these original 46 chromosomes duplicate again and
again to pass on the same genetic information to each new cell in the
developing child. Human chromosomes are large enough to be seen
with a light microscope, and the 23 pairs can be identified according
to differences in their size, shape, and the way they pick up special
laboratory dyes.
 
Genetic Problems
 
Genetic problems can happen for many different reasons. Sometimes
a mistake occurs during cell division, causing an error in chromosome
number either before or shortly after conception. The developing embryo
grows from cells that have either too many chromosomes or too few.
In "trisomy," for example, there are three copies of one particular
chromosome instead of the normal two (one from each parent). Down
syndrome, trisomy 18 (Edwards) syndrome, and trisomy 13  (Patau)
syndrome are all examples of this type of genetic problem. In "monosomy,"
another form of number error, one member of a chromosome pair is
missing. There are too few chromosomes rather than too many.
 
Sometimes it's not the number of chromosomes that's the problem.
Instead, one or more chromosomes is incomplete or abnormally shaped.
In both deletions and microdeletions, for example, some small part of a
chromosome is missing. In a microdeletion, the missing part of a chromosome
is usually so small that it amounts to only a single gene. Some important
genetic disorders caused by deletions and microdeletions include:
Wolf-Hirschhorn syndrome (affects chromosome 4); Cri-du-chat syndrome
(chromosome 5); DiGeorge syndrome (chromosome 22); and Williams
syndrome (chromosome 7).
 
In translocations, bits of chromosomes shift from one chromosome to
another, while in inversions, small parts of the DNA code seem to be
snipped out and reinserted backwards.
 
Very special types of genetic problems also occur when abnormalities
affect the sex chromosomes. Normally, a child will be a male if he inherits
one X chromosome from his mother and one Y chromosome from his father. 
A child will be a female if she inherits a double dose of X (one from each
parent),and no Y. Sometimes, however, children are born with only one
sex chromosome (usually a single X), or with an XXY or XYY inheritance.
Sometimes, too, a genetic problem is sex-linked, meaning that it is carried
by either the X or Y chromosome.
 
Some genetic problems are caused by a single gene that is present but
abnormal. When this is the case, chromosome number and appearance
are often entirely normal. To pinpoint the defective gene, scientists use
sophisticated DNA screening techniques.  Some examples of genetic
illnesses caused by a single problem gene include: cystic fibrosis, sickle
cell anemia, Tay-Sachs disease, and achondroplasia (a type of dwarfism).
 
Although experts originally believed that no more than three percent of
all human diseases were caused by errors in a single gene, new research
suggests that this may be an underestimate. Within the last two years,
scientists have discovered genetic links to many different diseases that
were not originally thought of as "genetic," including several different types
of cancer. They have identified 20 to 30 "cancer susceptibility genes" that
greatly increase a person's odds of getting some form of malignancy.
 
For example, a gene has been identified on chromosome number 9 that
may be linked to a common skin cancer called basal cell carcinoma. This
gene, labeled PTC or "patched," may someday be important in screening
for the cancer. Another gene, called HNPCC, is carried by one out of every
300 Americans and may greatly increase an individual's chance of getting
colon cancer. And the doubly dangerous gene called BRCA-1 seems to give
women an 85% chance of developing breast cancer, as well as a 50%
chance of ovarian tumors.
 
Altered genes may also play a role in the development of many other
devastating illnesses besides cancer. Parkinson's disease, for example, may
be linked to a gene on chromosome number 4, and multiple sclerosis may
be linked to alterations in a gene on chromosome number 6. Alzheimer's
disease, linked to the ApoE4 gene on chromosome 19, can already be
diagnosed (in some cases) by screening for that altered gene.
 
Although heart disease and diabetes appear to be related to simultaneous
changes in many different genes, the first of these, called LpL PvuII, may
already have been identified. According to American Heart Association reports,
this gene may be an "artery-clogging gene" that almost doubles the risk of
fatty deposits blocking the coronary arteries. Having the LpL PvuII gene may
also triple someone's changes of getting adult-onset diabetes. Like heart
disease, depression and other mental illnesses may be the result of alterations
in several genes at once. Although no specific genes have yet been found,
doctors estimate that 48-75% of depression is inherited, and they believe that
they will find the exact genetic mechanism very soon.
 
It is important to note that much of the newest information from genetic research
has not yet been translated into useful screening tests for your doctor's office.
However, experts predict that this will soon change, and they estimate that the
number of available genetic tests will increase tenfold in the next decade.
 
Genetic Testing
 
At one time doctors could only diagnose genetic problems by karyotyping - checking
the number, shape, and dye stains in chromosomes. Now genetic testing has
developed far enough to allow doctors to pinpoint missing or defective genes. The
type of genetic test needed to make a specific diagnosis depends on the particular
genetic illness that your doctor suspects. If he or she suspects a trisomy, for example,
a simple chromosome check will probably be enough. If the problem is a single
problem gene, however, more high-tech DNA screening will usually be necessary.
For genetic testing in children before birth, chorionic villus sampling or amniocentesis
is usually performed.
 
Many different types of body fluids and tissues can be used in genetic testing.   For
DNA screening, only a very tiny bit of blood, skin, bone, or other tissue is needed.
Even the small amount of tissue at the bottom end of a human hair is usually enough.
 
When Do Doctors Recommend Genetic Testing?
 
A doctor may recommend genetic testing for any of the following reasons:
  • A couple is planning to start a family and one of them or a close relative
    has an inherited illness. Some people are carriers of genetic illnesses, even
    though they do not suffer from the illness themselves. This happens because
    some genetic illnesses are recessive - they are only expressed if a person
    inherits two doses of the problem gene, one from each parent. Someone who
    inherits one problem gene from one parent but a normal gene from the other
    parent will not have symptoms of a recessive illness but will have a 50-50
    chance of someday passing the problem gene to their own children.

  • An individual already has one child with a severe birth defect.
    Not all children who suffer from birth defects have genetic problems.
    Sometimes birth defects are caused by exposure to a toxin (poison),
    infection, or physical trauma before birth. Even if a child does have
    a genetic problem, there is always a chance that it was not inherited,
    that it happened because of some spontaneous error in the child's
    cells, not the parents'.

  • A woman has had two or more miscarriages.
    Severe chromosome problems in the fetus can sometimes lead to
    a spontaneous miscarriage. Several miscarriages may point to a
    genetic problem.

  • A woman has delivered a stillborn child with physical signs
    of a genetic illness.
    Many serious genetic illnesses cause
    specific physical abnormalities that give an affected child a
    very distinctive appearance.
  • A woman is pregnant and over age 34.
    Chances of having a child with Down syndrome increase dramatically
    when a pregnant woman is older.

  • A child has medical problems that might be genetic.
    When a child has medical problems involving more than one
    body system, genetic testing may be recommended to identify
    the cause and make a diagnosis.

  • A child has medical problems that are recognized as a specific genetic syndrome.
    Genetic testing is performed to confirm the diagnosis.  In some cases
    it also may aid in identifying the specific type or severity of a genetic
    illness, which can help identify the most appropriate treatment.

A Word of Caution

Although advances in genetic testing have created a revolution in the way
that doctors diagnose and treat certain illnesses, there are still some limits
that parents need to recognize. First, although genetic tests can identify a
particular problem gene, they cannot always predict how severely that gene
will affect the person who carries it. In cystic fibrosis, for example, finding a
problem gene on chromosome number 7 cannot necessarily predict whether
a child will have serious lung problems or only mild respiratory symptoms.
 
Second, since many illnesses develop from a deadly mix of high-risk genes and
unhealthy lifestyle (for example, a smoker with a family history of heart disease),
simply having problem genes is only half the story. Knowing that you carry high
-risk genes may actually be an advantage, if it gives you the chance to modify
your lifestyle to avoid becoming sick.

A Great Potential

 
Every day researchers are finding new evidence that people who have specific
genes are at a greater risk for illnesses like cancer, heart disease, psychiatric
disorders, and many other medical problems. The next step is to discover just
how these problem genes work. Once we learn this, it may be possible to develop
specific types of gene therapy to prevent some of humanity's major killer diseases.
 
Right now, gene therapy is already being used successfully to treat cystic fibrosis
and ADA deficiency (an immune deficiency). Sickle cell anemia, the thalassemias,
and other blood disorders may be the next targets for a genetic cure. Although
genetic treatments for major killers, like cancer, may be a long way off, there is
still great hope that many more genetic cures will be found. In less than ten years,
scientists working on the Human Genome Project will have finished identifying and
mapping out all of the genes (up to 100,000) carried in our human chromosomes.
The map will be just a beginning, but it's a very hopeful beginning.  

More Information

DNA

DNA is deoxyribonucleic acid, the molecule that carries the codes for genetic
information. DNA is made of linked subunits called nucleotides. Each nucleotide
contains a phosphate molecule, a sugar molecule (deoxyribose), and one
of four coding molecules called bases (adenine, guanine, cytosine, or thymine).
The sequence of these four bases determines the genetic code.

Enzymes

Enzymes are proteins that act as natural catalysts. They help to direct and
control the chemical reactions that happen within the body.

Down syndrome

Down syndrome is a trisomy of chromosome number 21, and it affects one
of every 600 to 800 newborns. Children with Down syndrome have a distinct
facial appearance, with eyes that slant upwards at the corners, a small flat
face, and a large tongue that tends to stick out. Down syndrome causes
varying degrees of mental retardation and is associated with an increased
risk for certain heart problems, intestinal atresia (part of the intestines
shriveled or missing), and acute leukemia.

Trisomy 18 (Edwards) syndrome

Trisomy 18 syndrome affects one out of every 8,000 newborns. Children with this
syndrome have a low birth weight and a small head, mouth, and jaw. Their hands
typically form closed fists with abnormal finger positioning. They may also have
malformations involving the hips and feet, heart and kidney problems, and mental
retardation. Only about five percent of these children live longer than one year.

Trisomy 13 (Patau) syndrome

Trisomy 13 syndrome affects one out of every 20,000 newborns. This syndrome
causes cleft lip, flexed fingers with extra digits, hemangiomas (blood vessel
malformations) of the face and neck, and many different structural abnormalities
of the skull and face. It can also cause malformations of the ribs, heart, abdominal
organs, and sex organs.

Deletions

A deletion happens when part of a chromosome is missing. Several different
syndromes have been linked to deletions of specific parts of chromosomes 4,
5, 9, 13, 18, and 21. For example, Wolf-Hirschhorn syndrome is caused by a
deletion of part of chromosome 4. Children born with this syndrome can have
abnormalities of the head and face, malformations of the heart, and mental
retardation.

Microdeletions

Microdeletions happen when a very small piece of a chromosome is missing.
Often the missing piece is so small that it involves only a single gene. Because
microdeletions cannot be seen with a simple light microscope, they must be
detected using sophisticated DNA studies. Syndromes caused by microdeletions
include: DiGeorge syndrome, Prader-Willi syndrome, Angelman syndrome,
and Williams syndrome.

Translocations

In translocations, small bits of chromosomes shift from one chromosome to another.
Translocations may either be inherited from a parent or arise spontaneously in a
child's own chromosomes. They affect one out of every 500 newborns. Translocations
typically cause no malformations or developmental problems in the children who
have them. However, when these children grow to adulthood and wish to become
parents, they may have an increased risk of miscarriage or chromosome abnormalities
in their own children.

Inversions

In a chromosome inversion, a small portion of a chromosome breaks off, then
reinserts backwards. Inversions affect about one out of every 100 newborns
and typically cause no malformations or developmental problems in the children
who have them. However, when these children grow to adulthood and wish
to become parents, they may have an increased risk of miscarriage or chromosome
abnormalities in their own children.

DNA screening

In DNA screening, laboratories use molecular probes to check for a specific
coding sequence along the length of a person's DNA molecule. This specific
coding sequence is usually one that has been linked to causing an inherited
disease.

Karyotyping

Karyotyping is a laboratory test that shows chromosome number and appearance.
In karyotyping, a photo is taken of a person's chromosomes as they appear under
a microscope.

Chorionic villus sampling

Chorionic villus sampling (CVS) is a test performed on a pregnant woman, usually
between the tenth and twelfth weeks of pregnancy. In CVS, the doctor removes
a small piece of the placenta to check for genetic problems in a child before birth.
Because chorionic villus sampling is an invasive test, there is a small risk that it
can induce a miscarriage.

Amniocentesis

Amniocentesis is a test performed on a pregnant woman, usually between her
sixteenth and eighteenth week of pregnancy. The doctor inserts a hollow needle
into the woman's abdomen to remove a small amount of amniotic fluid from
around the developing fetus. This fluid can be tested to check for genetic problems
and to determine the sex of the child. When there is risk of cesarean section or
premature birth, amniocentesis may also be done to see how far the child's lungs
have matured. Like chorionic villus sampling, amniocentesis carries a slight risk
of inducing a miscarriage.

Reviewed by: Charles Scott, MD, and Linda Nicholson, MS, MC
Date reviewed: February 2000

Source:  KidsHealth www.KidsHealth.com is a project of The Nemours Foundation which is dedicated to improving the health and spirit of children. Today, as part of its continuing mission, the Foundation supports the operation of a number of renowned children's health facilities throughout the nation, including the Alfred I. duPont Hospital for Children in Wilmington, Delaware, and the Nemours Children's Clinics throughout Florida. Visit The Nemours Foundation to find out more about them and its health facilities for children http://www.nemours.org/no/