What Is Cystic Fibrosis?

Cystic Fibrosis

Cystic fibrosis (CF) is an inherited disease of your mucus and sweat glands. It affects mostly your lungs, pancreas, liver, intestines, sinuses, and sex organs.

Normally, mucus is watery. It keeps the linings of certain organs moist and prevents them from drying out or getting infected. But in CF, an abnormal gene causes mucus to become thick and sticky.

The mucus builds up in your lungs and blocks the airways. This makes it easy for bacteria to grow and leads to repeated serious lung infections. Over time, these infections can cause serious damage to your lungs.

The thick, sticky mucus can also block tubes, or ducts, in your pancreas. As a result, digestive enzymes that are produced by your pancreas cannot reach your small intestine. These enzymes help break down the food that you eat. Without them, your intestines cannot absorb fats and proteins fully.

As a result:

 Nutrients leave your body unused, and you can become malnourished.

 Your stools become bulky.

 You may not get enough vitamins A, D, E, and K.

 You may have intestinal gas, a swollen belly, and pain or discomfort.

The abnormal gene also causes your sweat to become extremely salty. As a result, when you perspire, your body loses large amounts of salt. This can upset the balance of minerals in your blood. The imbalance may cause you to have a heat emergency.

CF can also cause infertility (mostly in men).

The symptoms and severity of CF vary from person to person. Some people with CF have serious lung and digestive problems. Other people have more mild disease that doesn't show up until they are adolescents or young adults.

Respiratory failure is the most common cause of death in people with CF.

Until the 1980s, most deaths from CF occurred in children and teenagers. Today, with improved treatments, people with CF live, on average, to be more than 35 years old. Research continues to look for:

 Better treatments

 A cure http://www.nhlbi.nih.gov/health/dci/Diseases/cf/cf_what.html Currently, there is no cure for cystic fibrosis (CF). However, technological advancements in medicine allow many individuals with CF to live into adulthood. However, CF patients who do live longer are at a higher risk of developing complications of the disease such as lung infections and bowel blockage. It is important to note, however, that the severity, number, and type of symptoms can vary widely from patient to patient. Additionally, because CF affects many different systems of the body, a wide variety of techniques and medications are used to treat the condition and its complications. While the treatment of CF depends upon the severity, stage, and progression of the disease; general goals are:

1. to ensure adequate calorie and nutrient consumption 2. to increase airflow in the lungs 3. to decrease the volume and thickness of lung mucus 4. to prevent/treat infection in the lungs

There are currently 115 Cystic Fibrosis Foundation (CFF) treatment centers scattered throughout the United States. These unique treatment centers specialize in diagnosing and treating cystic fibrosis. For more information regarding CFF treatment centers, you can visit the following link: http://www.cff.org.

Nonpharmacologic (non-drug) therapies

Nutrition/Exercise

CF patients often do not absorb enough calories, protein, and vitamins from their usual daily diet to maintain adequate nutrition. As a result, individuals with CF are advised to increase their daily intake of calories to 120%-150% of the recommended daily allowance (RDA). CF patients should also increase the amount of protein in their usual daily diet by 200% of the RDA of protein. Nutritional supplements, such as Ensure, Sustical, and Scandishakes, may help CF patients maintain the amount of nutrients they require each day.

CF patients should exercise as tolerated to help loosen mucus build-up so that it may be removed more easily. Exercise also helps to expand the lungs and increase lung capacity (amount of air the lungs are able to hold). However, exercise may not be appropriate for all CF patients. It is important for patients to talk with their doctor before beginning to exercise.

Chest physiotherapy/postural drainage/percussion/chest vest

Because CF can cause patients to produce abnormally thick and sticky mucus, a variety of methods are available to help remove the secretions. Postural drainage is an alternative process used to help clear mucus from the lungs by altering the patient's position. Classic techniques, such as chest percussion (tapping on the chest and back) and the chest vest (a vibrating vest) have also been used to help dislodge and remove excessive mucus in the lungs of CF patients. In addition, innovative breathing devices, such as oscillatory positive expiratory pressure (OPEP) devices (such as the Acapella and the Flutter) can be used to loosen mucus. By exhaling into the OPEP device, vibrations are created which help move the abnormal secretions from the lungs.

Oxygen & Transplant

In severe cases of CF, the patient's damaged lung function could become life-threatening necessitating the need for an oxygen machine. If the physician determines that the patient is a good candidate for transplantation, he/she will be put on a lung transplant waiting list. It should be noted, however, that a lung transplant will not cure CF. Patients with the following conditions should not be considered for lung transplantation:

 Cancer  HIV infection  Major psychiatric illness  Severe damage to other body organs  Severe overweight

Pharmacological (drug) treatment

Digestive Enzymes

In patients with CF, defects of a gene known as CFTR alter the function of a protein that regulates ion transport, which is the normal movement of sodium, chloride, and water in the body. This alteration causes secretions to be abnormally heavy, thick, and sticky. Normally in healthy people, the pancreas is a gland that produces digestive enzymes (proteins that help break down food such as amylase, protease, and lipase) which are excreted through small channels into the small intestine when food is present. However, the abnormal mucus in CF patients clogs these channels in the pancreas, resulting in an insufficient amount of digestive enzymes in the stomach. As a result, food is not digested correctly and intestinal problems such as diarrhea and bowel blockage occur. Because CF patients usually do not have enough digestive enzymes in their intestines to break down the food they eat, they must take supplemental oral digestive enzymes. Ordinarily, digestive enzymes are taken with every meal or snack in often large doses.

Bronchodilators

Maintaining adequate airflow is important to CF patients because a reduction in the ability to breathe can often cause a great deal of anxiety as well as hypoxemic (lack of oxygen) complications. If CF patients do not obtain enough oxygen, the organs (such as the brain) of the patient are at great risk for obtaining damage. To combat this potential problem inhaled bronchodilators have been widely used to help maintain adequate airflow and lessen the breathing difficulties that CF patients experience.

Inhaled/oral corticosteroids and ibuprofen As a result of the numerous lung infections that CF patients experience, chronic inflammation of the lung tissue can occur. If the lung tissue remains inflamed for a great deal of time (days-months), damage can occur, thus resulting in the loss of lung function. In order to decrease the amount of lung inflammation, drugs such as corticosteroids (natural hormones normally made by the adrenal gland) can be prescribed. By decreasing the frequency and severity of lung inflammation, corticosteroids (such as prednisone) may prevent future lung problems. Non-steroidal anti-inflammatory drugs such as ibuprofen are another group of drugs that may help decrease the severity of symptoms in CF patients by decreasing inflammation. Because of potentially severe side effects, it is only appropriate to take ibuprofen exactly as your physician prescribes.

Mucolytic or Mucus-thinning drugs

Since CF causes patients to produce abnormally thick and sticky mucus, drugs that thin the mucus can be given to patients. Thin mucus is easier to be cleared from the lungs of individuals with CF, thus allowing them to breathe easier. For example, a drug called DNase (also known as recombinant human deoxyribonuclease or dornase alfa) works to thin mucus by breaking apart the genetic material (DNA) contained in the abnormally thick secretions. This action decreases the viscosity (thickness) of the secretions, therefore allowing the mucus to be easily cleared.

Antibiotics

Lung infections, in general, are difficult to control and cure. In CF patients, however, the challenge to treat lung infections increases. The bacteria that cause these lung infections are able to multiply and flourish in the presence of the sticky and thick secretions found in individuals with CF. Mucus can also prevent antibiotics from reaching the infection site, consequently making it more difficult to treat. In light of this complicated situation, new inhaled and oral (tablets and capsules) antibiotics have been developed to help control recurrent lung infections in CF patients. http://www.drugdigest.org/DD/HC/Treatment/0,4047,851,00.html Down Syndrome

What is Down Syndrome? Down syndrome is set of mental and physical symptoms that result from having an extra copy of Chromosome 21.

Normally, a fertilized egg has 23 pairs of chromosomes. In most people with Down syndrome, there is an extra copy of Chromosome 21 (also called trisomy 21 because there are three copies of this chromosome instead of two), which changes the body’s and brain’s normal development.

(For more information on chromosomes, see Cells 101.)

What are the signs and symptoms of Down syndrome? Even though people with Down syndrome may have some physical and mental features in common, symptoms of Down syndrome can range from mild to severe. Usually, mental development and physical development are slower in people with Down syndrome than in those without the condition.

Mental retardation is a disability that causes limits on intellectual abilities and adaptive behaviors (conceptual, social, and practical skills people use to function in everyday lives). Most people with Down syndrome have IQs that fall in the mild to moderate range of mental retardation. They may have delayed language development and slow motor development.

Some common physical signs of Down syndrome include:

← Flat face with an upward slant to the eye, short neck, and abnormally shaped ears ← Deep crease in the palm of the hand ← White spots on the iris of the eye ← Poor muscle tone, loose ligaments ← Small hands and feet

There are a variety of other health conditions that are often seen in people who have Down syndrome, including:

← Congenital heart disease ← Hearing problems ← Intestinal problems, such as blocked small bowel or esophagus ← Celiac disease ← Eye problems, such as cataracts ← Thyroid dysfunctions ← Skeletal problems ← Dementia—similar to Alzheimer’s

What is the treatment for Down syndrome? Down syndrome is not a condition that can be cured. However, early intervention can help many people with Down syndrome live productive lives well into adulthood.

Children with Down syndrome can often benefit from speech therapy, occupational therapy, and exercises for gross and fine motor skills. They might also be helped by special education and attention at school. Many children can integrate well into regular classes at school. For more information about treatments for Down syndrome, visit one of the Web sites provided below or ask your health care provider. Who is at risk for Down syndrome? The chance of having a baby with Down syndrome increases as a woman gets older—from about 1 in 1,250 for a woman who gets pregnant at age 25, to about 1 in 100 for a woman who gets pregnant at age 40. But, most babies with Down syndrome are born to women under age 35 because more younger women have babies.

Because the chances of having a baby with Down syndrome increase with the age of the mother, many health care providers recommend that women over age 35 have prenatal testing for the condition. Testing the baby before it is born to see if he or she is likely to have Down syndrome allows parents and families to prepare for the baby’s special needs.

Parents who have already have a baby with Down syndrome or who have abnormalities in their own chromosome 21 are also at higher risk for having a baby with Down Syndrome.

Once the baby is born, a blood test can confirm whether the baby has Down syndrome.

http://www.nichd.nih.gov/health/topics/Down_Syndrome.cfm Sickle Cell Anemia

Sickle cell anemia is a disease in which your body produces abnormally shaped red blood cells. The cells are shaped like a crescent or sickle. They don't last as long as normal, round red blood cells, which leads to anemia. The sickle cells also get stuck in blood vessels, blocking blood flow. This can cause pain and organ damage.

A genetic problem causes sickle cell anemia. People with the disease are born with two sickle cell genes, one from each parent. If you only have one sickle cell gene, it's called sickle cell trait. About 1 in 12 African Americans has sickle cell trait. A blood test can show if you have the trait or anemia. Most states test newborn babies as part of their newborn screening programs.

Bone marrow transplant offers the only potential cure for sickle cell anemia. But very few people have a suitable donor for transplant.

As a result, treatment for sickle cell anemia is usually aimed at avoiding crises, relieving symptoms and preventing complications. If you have sickle cell anemia, you'll need to make regular visits to your doctor to check your red blood cell count and monitor your health. You may also require treatment from specialists at a hospital or sickle cell anemia clinic. Treatments may include medications to reduce pain and prevent complications, blood transfusions and supplemental oxygen, as well as bone marrow transplant.

http://www.mayoclinic.com/health/sickle-cell- anemia/DS00324/DSECTION=treatments-and-drugs Haemophilia

The list of signs and symptoms mentioned in various sources for Hemophilia includes the 12 symptoms

listed below:

← Symptoms range in severity from mild to severe ← Bleeding ← Bruising ← Bruising easily ← Clotting difficulty ← Hemorrhage ← Excessive bleeding from wounds ← Excessive bleeding after injury ← Bleeding into joints ← Bleeding into muscles ← Intracranial bleeding - from minor head injury ← Internal bleeding - in severe cases

http://www.wrongdiagnosis.com/h/hemophilia/symptoms.htm

How do you get haemophilia?

In most cases, haemophilia is inherited and affects mostly men. Women can carry the gene that causes haemophilia. When a woman who is a carrier has children, she has a 50% chance that her sons will develop haemophilia and a 50% chance that her daughters will become carriers. While sons of men with haemophilia will not inherit the disease, all daughters born to fathers who have haemophilia will be carriers. In addition, in about one third of all cases, there is no family history of the disease and haemophilia occurs as the result of a new gene mutation.

http://www.novonordisk.com.au/documents/article_page/document/HaemHCP_FA Q_HowdoyougetHaemophilia.asp How Is Hemophilia Treated?

Treatment With Replacement Therapy

The main treatment for hemophilia is called replacement therapy—giving or replacing the clotting factor that’s too low or missing. Concentrates of clotting factor VIII (for hemophilia A) or clotting factor IX (for hemophilia B) are slowly dripped in or injected into a vein. http://www.nhlbi.nih.gov/health/dci/Diseases/hemophilia/hemophilia_treatments.html Cri Du Chat

Signs and symptoms

The syndrome gets its name from the characteristic cry of infants born with the disorder. The infant sounds just like a meowing kitten, due to problems with the larynx and nervous system. This cry identifies the syndrome. About 1/3 of children lose the cry by age 2. Other symptoms of cri du chat syndrome may include:

 feeding problems because of difficulty swallowing and sucking,  low birth weight and poor growth,  severe cognitive, speech, and motor delays,  behavioral problems such as hyperactivity, aggression, tantrums, and repetitive movements,  unusual facial features which may change over time.  excessive dribbling.

http://en.wikipedia.org/wiki/Cri_du_chat

Treatment No treatment exists for the underlying genetic disorder, so medical care is focused on the symptoms. Chronic medical problems, such as respiratory tract infections, may occur and require treatment. Heart defects may need to be corrected by surgery. The child with cri-du- chat syndrome may require a gastrostomy tube for feeding.

To increase communication skills, early intervention by a speech therapist can help the child learn to use sign language. Behavior modification programs can help families manage the child's behavior problems, often a source of stress for the family.

http://rarediseases.about.com/cs/criduchatsynd/a/010704.htm

Who gets it? Cri-du-chat syndrome is a genetic disorder caused by partial deletion (loss) of part of human Chromosome 5 (known as 5p-). This chromosome error occurs during fetal development and is not inherited. The estimated incidence of the syndrome in the United States is 1 in 50,000 live births. Cri-du-chat syndrome affects people of all ethnic backgrounds.

Muscular Dystrophy

Duchenne muscular dystrophy (DMD) is a severe recessive x-linked form of muscular dystrophy that is characterized by rapid progression of muscle degeneration, eventually leading to loss in ambulation, paralysis, and death. This affliction affects one in 3500 males, making it the most prevalent of muscular dystrophies. In general, males are only afflicted, though females can be carriers. The disorder is caused by a mutation in the gene DMD, located in humans on the X chromosome. The DMD gene codes for the protein dystrophin, an important structural component within muscle tissue. Dystrophin provides structural stability to the dystroglycan complex (DGC), located on the cell membrane.

Symptoms usually appear in male children before age 6 and may be visible in early infancy. Progressive proximal muscle weakness of the legs and pelvis associated with a loss of muscle mass is observed first. Eventually this weakness spreads to the arms, neck, and other areas. Early signs may include pseudohypertrophy (enlargement of calf muscles), low endurance, and difficulties in standing unaided or inability to ascend staircases. As the condition progresses, muscle tissue experiences wasting and is eventually replaced by fat and fibrotic tissue (fibrosis). By age 10, braces may be required to aide in walking but most patients are wheelchair dependent by age 12. Later symptoms may include abnormal bone development that lead to skeletal deformities, including curvature of the spine. Due to progressive deterioration of muscle, loss of movement occurs eventually leading to paralysis. Intellectual impairment may also be present but does not progressively worsen as the child ages. The average life expectancy for patients afflicted with DMD varies from early teens to age mid 30s. There have been reports of DMD patients surviving past the age of 40 and even 50.

There is no known cure for Duchenne muscular dystrophy, although recent stem-cell research is showing promising vectors that may replace damaged muscle tissue. Fragile X Syndrome

What is Fragile X syndrome? Fragile X syndrome is the most common form of inherited mental retardation.

Fragile X happens when there is a change, or mutation, in a single gene called the Fragile X Mental Retardation 1 (FMR1) gene. This gene normally makes a protein the body needs for the brain to develop. But when there is a change in this gene, the body makes only a little bit or none of the protein, which can cause the symptoms of Fragile X.

Fragile X is inherited, which means it is passed down from parents to children. Parents can have children with Fragile X even if the parents do not have Fragile X themselves. The changes in the gene can become more serious when passed from parent to child.

Some people may only have a small change in their FMR1 gene (called a premutation) and may not show any signs of Fragile X. Other people may have bigger changes in the gene, called a full mutation, that cause the symptoms of Fragile X Syndrome.

For more information about genes and chromosomes, see Cells 101.

What are the signs and symptoms of Fragile X syndrome? Not everyone with Fragile X has the same signs and symptoms, but they do have some things in common. Symptoms are often milder in girls than in boys. Here are some common signs of Fragile X:

← Intelligence and learning – Many people with Fragile X have intellectual disabilities. These problems can range from mild learning disabilities to more severe mental retardation. ← Physical – Teens and adults with Fragile X may have long ears, faces, and jaws. Many people with Fragile X may also have loose, flexible joints. They may have flat feet and be able to extend joints like the thumb, knee, and elbow further than normal. ← Social and Emotional – Most children with Fragile X have some behavior challenges. They may be afraid or anxious in new situations. Many children, especially boys, have trouble paying attention or may be aggressive. Girls may be shy around new people. ← Speech and Language – Most boys with Fragile X have some problems with speech and language. They may have trouble speaking clearly, or may stutter, or leave out parts of their words. They may also have problems understanding “clues” when talking to other people, such as understanding the speaker’s tone of voice or that person’s body language. Girls usually do not have severe problems with speech or language. ← Sensory – Many children with Fragile X are bothered by certain sensations, such as bright light, loud noises, or the way something feels. Some do not like to be touched, or have trouble making eye contact with other people

For more specific information about symptoms, check out the What are the Signs and Symptoms of Fragile X Syndrome? section of the NICHD booklet Families and Fragile X Syndrome.

What are the treatments for Fragile X syndrome? There is no cure for Fragile X, but there are ways to help with the symptoms. People with Fragile X can get help to reduce or eliminate some of the learning, physical, social and emotional, speech and language, and sensory problems common in Fragile X. The sooner those with Fragile X get help, the more they can learn and the better their outcomes.

Huntington’s Disease

What is Huntington's Disease?

Huntington's Disease (HD) is a brain disorder that affects a person's ability to think, talk, and move.

The disease destroys cells in the basal ganglia, the part of the brain that controls movement, emotion, and cognitive ability. HD is caused by a mutation in a gene on chromosome 4. The job of its protein product, huntingtin, is to direct the delivery of small packages (vesicles containing important molecules) to the outside of the cell. Normally, the coding region of this gene contains the DNA sequence "CAG" repeated again and again. The number of times this triplet is repeated varies from person to person, ranging from 10 to 26 times. People with HD have an abnormally high number of these CAG triplets, approximately 40 or more. This likely disrupts the function of the gene's protein product, but how the expansion of the CAG repeat causes disease is unknown. Somehow the brain cells of HD patients accumulate clumps of protein that become toxic, resulting in cell death. Some patients lose more than 25% of their brain cells before they die.

How do people get Huntington's Disease?

Huntington's disease is inherited in an autosomal dominant pattern. This means that everyone who inherits the faulty gene will eventually get the disease. A parent with a mutation in the HD gene has a 50 percent chance of passing on the disease to their children. What are the symptoms of Huntington's Disease?

Huntington's disease affects the part of the brain that controls thinking, emotion, and movement. Most people who have the disease start to see symptoms between the ages of 30 and 50 (but symptoms can appear earlier or later in life). The disease gets worse over time.

Some of the symptoms include: poor memory, depression and/or mood swings, lack of coordination, twitching or other uncontrolled movements, and difficulty walking, speaking, and/or swallowing. In the late stages of the disease, a person will need help doing even simple tasks, such as getting dressed.

How do doctors diagnose Huntington's Disease?

During pregnancy a woman can find out if her baby will have the disease with two tests: taking a sample of fluid from around the fetus (amniocentesis), or by taking a sample of fetal cells from the placenta (chorionic villus sampling (CVS)).

After the child is born, doctors can identify the disease by first doing a series of neurological and psychological tests. A genetic test can then confirm the diagnosis by determining if the person indeed has inherited the HD gene mutation (an expansion of the CAG triplet). However, the test cannot tell at what age a person will begin to get sick.

How is Huntington's Disease treated?

Treatments do not slow the progression of the disease, but they can help make the patient more comfortable.

Medications ease feelings of depression and anxiety; others control involuntary movements.

Physical or speech therapy helps HD patients lead more normal lives. What is Severe Combined Immunodeficiency (SCID)?

SCID is a group of very rare-and potentially fatal-inherited disorders related to the immune system. The immune system normally fights off attacks from dangerous bacteria and viruses. People with SCID have a defect in their immune system that leaves them vulnerable to potentially deadly infections.

There are several types of SCID. The most common form is caused by a mutation in the SCIDX1 gene located on the X chromosome. This gene encodes a protein that is used to construct a receptor called IL2RG (interleukin-2 receptor). These receptors reside in the plasma membrane of immune cells. Their job is to allow two types of immune cells - T cells and B cells - to communicate. When the gene is mutated, the receptors cannot form and are absent from immune cells. As a result, the immune cells can't communicate with one another about invaders in the environment. Not enough T and B cells are produced to fight off the infection, and the body is left defenseless.

Another form of SCID is caused by a mutation on chromosome 20 and is characterized by a deficiency of the enzyme adenosine deaminase (see ADA Deficiency).

How do people get SCID?

The most common form of SCID exhibits an X-linked recessive pattern of inheritance, and is therefore referred to as X-linked SCID. When a gene is located on the X chromosome, males are more often affected than females. Males do not have a second X chromosome to compensate for the defective one. They only need to inherit one bad copy of the gene to have the symptoms of the disorder. Females, on the other hand, have two X chromosomes. If they inherit one defective X chromosome, they still have its healthy pair. They don't develop symptoms of the disorder, but they still carry the faulty gene and can pass it on to their children. /p>

What are the symptoms of SCID?

Symptoms usually appear in the first few months of life. Because the immune system cannot protect the baby's body, babies with the disorder tend to get one infection after another. Some of these bacterial infections may be life-threatening, including pneumonia (lung infection), meningitis (brain infection), and sepsis (blood infection). To make matters worse, SCID patients often don't respond to the antibiotics used to treat bacterial infections. They may suffer more frequently from ear infections, sinus infections, a chronic cough, and rashes on the skin.

Early diagnosis of SCID is very important, because without quick treatment, children with the disease aren't likely to live past age 2.

How do doctors diagnose SCID?

SCID can be identified before the baby is born by removing and testing cells from the placenta (chorionic villus sampling or CVS), or by removing and testing a sample of the fluid surrounding the baby (amniocentesis).

Most babies are diagnosed with SCID in the first 6 months of life. The most common screening methods are an immune function test, and a blood test that detects low white blood cell counts, as well as low levels of immune cells (T cells and B cells).

How is SCID treated?

Children with SCID must be careful to stay away from germ- rich environments (such as day care centers and crowded shopping malls) where they could pick up a potentially life-threatening infection. The most effective treatment is a bone marrow transplant. Unspecialized stem cells (that will form blood and immune cells) are taken from the bone marrow of a healthy donor and injected into the SCID patient. Ideally, these new cells will stimulate the production of the needed immune cells. Transplants done within the first few months of life are most successful. The tissue must be "matched" to the patient, however, which can limit the usefulness of this therapy. Siblings make the best donors as their cells likely contain a similar genetic makeup.

Gene therapy for this disorder may soon be possible. This therapy would compensate for the faulty gene by injecting healthy copies of the gene into a patient's bone marrow stem cells.

Interesting facts about SCID

About 1 out of every 100,000 babies is born with SCID.

SCID is sometimes called Bubble Boy disease. In the 1970s, a boy named David Vetter had to live in a plastic bubble for 12 years because of SCID. Klinefelter’s Syndrome

What are the symptoms of Klinefelter syndrome?

Many people with this disorder have no idea they have it until they hit puberty or try to have children. At puberty, men with this syndrome often develop more breast tissue than normal, have a less muscular body, and grow very little facial or body hair. When men with Klinefelter syndrome try to have children, most discover that they are sterile because they cannot produce sperm. Learning disabilities (not categorized as mental retardation) are also a common problem for them.

How do doctors diagnose Klinefelter syndrome?

Klinefelter syndrome is most often diagnosed in adulthood using a karyotype, an analysis of the patient's chromosomes taken from a blood sample.

Klinefelter syndrome may also be diagnosed during a woman's pregnancy. Doctors can look for the chromosome abnormality in cells taken from the amniotic fluid that surrounds the fetus (amniocentesis), or from the placenta (chorionic villus sampling (CVS)).

How is Klinefelter syndrome treated?

Hormone replacement therapy is the best way to treat this disorder. Teenagers are typically given testosterone injections to replace the hormone that would normally be produced by the testes. Synthetic testosterone works like natural testosterone - it builds muscle and increases hair growth.

Interesting facts about Klinefelter syndrome

Klinefelter syndrome is one of the most common genetic abnormalities. It affects between 1 in 500 and 1 in 1,000 males.

The disorder is named for Dr. Harry Klinefelter, who first reported its symptoms in 1942. What is galactosemia?

Galactosemia is a rare disorder that affects the body's ability to break down a food sugar called galactose (found in milk and other dairy products).

Normally, the body breaks down lactose into galactose and then into glucose (a sugar used for energy). People with galactosemia are missing an enzyme called GATL (galactose-1-phosphate uridyl transferase), which normally converts galactose into glucose. Without this enzyme, harmful amounts of galactose build up in the blood. How do people get galactosemia?

The most common form of the disorder, classic galactosemia, is passed down in an autosomal recessive pattern. To get the disorder, a child must inherit one defective gene from each parent. Inheriting one normal gene and one mutated gene makes a person a carrier. A carrier produces less of the GALT enzyme than normal, but is still able to break down glucose and avoid having symptoms of galactosemia. However, carriers can still pass on the mutated gene to their children.

What are the symptoms of galactosemia?

The build-up of galactose in the body can cause several severe symptoms: kidney failure, an enlarged liver, cataracts (clouding of the eye lens), poor growth, and mental retardation.

People can inherit a milder form of the disorder when a different gene, also involved in galactose metabolism, is mutated. These patients often suffer from cataracts, but not the other symptoms associated with classical galactosemia.

How do doctors diagnose galactosemia?

In most states, babies are tested for galactosemia at birth. Using a tiny blood sample taken from the baby's heel, the test checks for low levels of the GALT enzyme. This allows for prompt treatment, which can substantially prevent the serious symptoms of this disorder. For those families with a history of the disorder, a doctor can determine during a woman's pregnancy whether her baby has galactosemia 1) by taking a sample of fluid from around the fetus (amniocentesis), or 2) by taking a sample of fetal cells from the placenta (chorionic villus sampling or CVS).

How is galactosemia treated?

The only way to treat galactosemia is through dietary restrictions. People with the disorder must stay away from foods and drinks containing galactose, including milk, cheese, and legumes (dried beans).

Interesting facts about galactosemia

Galactosemia was first discovered in 1908 by the physician Von Ruess.

Classical galactosemia affects 1 in every 55,000 newborns. What is Alzheimer's disease?

Alzheimer's is a disease that causes dementia, or loss of brain function. It affects the parts of the brain that deal with memory, thought, and language.

The brain of a person with Alzheimer's contains abnormal clumps of cellular debris and protein(plaques) and collapsed microtubules (support structures of the cell). Microtubule disintegration is caused by a malfunctioning protein called tau, which normally stabalizes the microtubules. In Alzheimer's patients, tau proteins instead cluster together to form disabling tangles. These plaques and tangles damage the healthy cells around them. The brain also produces smaller amounts of neurotransmitters (acetylcholine, serotonin, and norepinephrine), chemicals that allow nerve cells to talk to one another. The most common form of the disease, which strikes after age 65, is linked to the apolipoprotein E (apoE) gene on chromosome 19. Scientists don't know how apoE4 increases the risk of developing Alzheimer's. They do know that everyone has apoE, which comes in three forms. One of the forms (apoE4) increases a person's risk of developing Alzheimer's. The other two forms seem to protect against the disease. While people who inherit the apoE4 form of the gene are at increased risk for the disease, they will not necessarily develop it.

Mutations in genes found on chromosomes 1, 14, and 21 are linked to rarer forms of the disease, which strike earlier in life.

How do people get Alzheimer's disease?

Scientists don't know exactly how people develop Alzheimer's, but they believe it is caused by a combination of genes and environmental factors (multifactorial disorder).

The early-onset forms of Alzheimer's are inherited in an autosomal dominant pattern, which means that only one parent has to pass down a defective copy of the gene for their child to develop the disorder.

What are the symptoms of Alzheimer's disease?

Because Alzheimer's destroys brain cells, people who have the disorder slowly lose their ability to think clearly. At first, they may forget words or names, or have trouble finding things. As the disorder worsens, they may forget how to do simple tasks (such as walking to a friend's house or brushing their hair). Some people with Alzheimer's also feel nervous or sad.

How do doctors diagnose Alzheimer's disease?

There is no one test for Alzheimer's. Doctors use several different tests to check a patient's memory, language skills, and problem solving abilities. These tests don't diagnose Alzheimer's, but they can rule out other disorders that have similar symptoms. How is Alzheimer's disease treated?

There is no cure for Alzheimer's, but a few medicines can slow its symptoms. A drug called Aricept increases the amount of the neurotransmitter acetylcholine in the brain. A new medicine, Namenda, protects brain cells from a chemical called glutamate, which can damage nerve cells. Doctors may also give their Alzheimer's patients antidepressants or anti-anxiety medicines to ease some of their symptoms.

People with Alzheimer's often need a caregiver - someone to help them get around and do the things they were once able to do themselves.

Interesting facts about Alzheimer's disease

Alzheimer's was named after the German doctor, Alois Alzheimer, who first named the disorder in 1906.

The older a person gets, the higher his or her risk of getting Alzheimer's. Only about 1 or 2 people out of 100 have Alzheimer's at age 65; whereas, one out of every five people has the disorder by age 80.

As many as 4 million Americans have Alzheimer's disease The thyroid is the largest endocrine gland in the body. It sits just below the larynx (voice box) and wraps around the trachea (windpipe). The thyroid gland produces thyroid hormone, which helps the body grow and develop. It also plays an important role in the body's metabolism (the processes in the body that use energy, such as eating, breathing, and regulating heat).

Hypothyroidism (or underactive thyroid) is a common condition in which the thyroid gland produces too little thyroid hormone. About 1 in 5,000 babies is born with congenital hypothyroidism, in which the thyroid fails to grow normally and cannot produce enough of its hormone. There is no known cause for most cases of congenital hypothyroidism. But about 10 to 20 percent of the time, the condition is caused by an inherited defect that alters the production of thyroid hormone.

The most common inherited form of hypothyroidism is a defect of the TPO (thyroid peroxidase) gene on chromosome 2. This gene plays an important role in thyroid hormone production.

How do people get hypothyroidism?

Hypothyroidism may be caused by 1) an autoimmune disease that attacks the thyroid gland, 2) surgery or radiation to treat thyroid cancer and other conditions, or 3) rare and random genetic events in which a mutation is acquired during early development.

What are the symptoms of hypothyroidism?

In babies with the inherited form of hypothyroidism, the condition affects growth and cognitive development. It may cause mental retardation, delayed puberty, stunted growth, and ataxia (inability to coordinate muscle movements).

In adults, hypothyroidism slows the body's metabolism, making the patient feel mentally and physically sluggish. Symptoms may include weakness, fatigue, muscle aches, mood swings, hair loss, memory loss, or slow speech. A person's symptoms will depend upon how little thyroid hormone they produce, and for how long they have had the disorder.

When the body is deprived of thyroid hormone, the pituitary gland works overtime, producing extra thyroid- stimulating hormone (TSH). This glut of TSH may enlarge the thyroid into a condition called a goiter. How do doctors diagnose hypothyroidism?

Babies are normally screened for hypothyroidism 24 hours after birth. A tiny sample of blood taken from the baby's heel is tested for low thyroid hormone levels or high thyroid-stimulating hormone (TSH) levels.

How is hypothyroidism treated?

Hormone replacement therapy: people with hypothyroidism must take a synthetic form of thyroid hormone every day to reduce their symptoms.

Interesting facts about hypothyroidism

One in 5,000 people has hypothyroidism.