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Below are the most recent content updates.
Androgen insensitivity syndrome (AIS) is a genetic disorder that affects sexual development before birth and during puberty. Individuals with AIS have one X and one Y chromosome making them genetically male, but they usually self-identify as female and have external female genitals. These individuals also do not grow facial hair or have other external male features during puberty. Individuals with AIS also experience infertility problems. Learn more.
✎ New: Fetal varicella syndrome
Fetal Varicella Syndrome is a group of birth defects that can include scars on the skin, eye problems, poor growth, underdevelopment of an arm or leg, small head size, delayed development and mental retardation. Some babies will only have one of the problems, while others have some, or all. These defects occur as a result of an infection with the virus that causes chicken pox, called Varicella zoster. Learn more.
Hutchinson-Gilford Progeria syndrome, or progeria, is a rare genetic condition that makes a person’s body seem to age much faster than expected. Children with progeria have trouble growing and gaining weight. Children typically experience medical issues that are usually associated with older age, such as hair loss, bone changes, hearing loss, joint stiffness, atherosclerosis (hardening of the arteries), and heart disease. As of June 14, 2016, there is no cure for progeria, but the symptoms and medical issues can be monitored and treated to increase a child’s quality of life. Learn more.
✎ New: Maple syrup urine disease
Maple syrup urine disease, MSUD, is an inherited metabolic disorder. It is named after the hallmark maple syrup odor of the urine that is caused by an accumulation of amino acids. The other features of MSUD are lethargy, poor feeding, muscle spasms, mental retardation, and developmental delay. MSUD has several sub-types that vary by severity and presentation. Treatment for MSUD is through dietary restriction of branched-chain amino acids and with treatment affected individuals may remain healthy and live through adulthood. Untreated MSUD will lead to seizures, coma and eventually death. Learn more.
✎ New: Otosclerosis
Otosclerosis is a condition that affects the ear. “Oto” means ear. “Sclerosis” means abnormal hardening of body tissue. Normally, bone is in a cycle of being continuously made and broken down. In otosclerosis, this process of making and breaking down bone is not done properly. When this happens, the bones in the middle ear get stuck in position and can’t vibrate when sound is coming through the middle ear. This prevents sound from travelling properly through the ear, and therefore impacts the person’s hearing. Learn more.
A spinal muscular atrophy (SMA) is one of a group of genetic conditions that affect the nerves, brain, and muscles in the body. In SMA, the nerves cells (motor nuclei) in the lowest region of the brain (lower brainstem) and nerve cells in the spinal cord (motor neurons) become more and more damaged and are unable to work correctly. The first symptoms of the nerve damage are usually “floppy” muscles that mean people can no longer sit up or use their arms and legs how they would like to. Muscles will continue to become weaker and weaker, slowly breaking down. This is called atrophy. As the disease gets worse, people will have increasing problems eating, swallowing, and breathing. Learn more.
Stickler syndrome is a genetic condition caused by a change (mutation) in genetic information that leads to abnormal development of connective tissue throughout the body. Connective tissue is an important part of many multiple organ systems. The specific health problems present in Stickler syndrome often are different from one individual to another and all of the symptoms may not occur in one person. Stickler syndrome is characterized by specific facial features, a hole in the roof of the mouth (cleft palate), eye and vision problems, hearing loss, and joint issues. Learn more.
► Updated: Kabuki syndrome
Kabuki syndrome is a rare genetic disorder that affects different parts of the body. It can be caused by changes in two different genes. Kabuki syndrome is caused by an error in the gene called KMT2D. Genes provide the instructions that control the body’s growth and development. When there is an error in the gene, the body develops differently. Learn more.
► Updated: Mucopolysaccharidosis Type I
Mucopolysaccharidosis type I (MPS I) is a progressive genetic disease that occurs when the level of an enzyme in the body, the alpha-L-iduronidase enzyme, is too low for it to do its job correctly (or absent completely). Alpha-L-iduronidase is involved in the breakdown of certain complex sugars in the body. These complex sugars are different from what we eat in our diet, and are called glycosaminoglycans (GAGs). Because the alpha-L-iduronidase enzyme level is too low, the GAGs called dermatan sulfate and heparan sulfate are not broken down and become stored in the lysosomes of the cells. Cells make up our entire body and all the tissues of our body; we have skin cells, heart cells, blood cells, etc. Learn more.
► Updated: Mucopolysaccharidosis Type III
Mucopolysaccharidosis type III (MPS III), also known as Sanfilippo syndrome, is a genetic condition in which a person is unable to break down large sugar molecules known as a glycosaminoglycans (GAGs). In MPS III, a specific GAG called heparan sulfate is unable to be broken down and builds up over time. Patients with MPS III usually appear normal at birth. Children may meet milestones up until age 2-6 and then start showing abnormal behaviors that get worse as the child gets older. At approximately 3-5 years of age most patients begin to develop mental and motor developmental delay, resulting in mental retardation. By age 10 other symptoms appear including wobbly and erratic gait and difficulty walking, aggressive behavior, stiff joints, skeletal abnormalities, hernias, enlarged liver and/or spleen (hepatosplenomegaly), hyperactivity, seizures, deafness, loss of vision, progressive dementia, and an inability to sleep for more than a few hours at a time. Most people with MPS III may survive into their teenage years, though some can survive into their twenties. Learn more.
► Updated: Mucopolysaccharidosis Type IVa
Mucopolysaccharidosis type (MPS) IV is a rare genetic disorder. This means that people have a problem in a specific gene. People have about 20,000-25,000 genes in their bodies. Genes are like our body’s instruction manual – they control the growth, development and normal function of the body. Because of a change in a specific gene, people with MPS IV lack an enzyme. This enzyme is needed to break down (metabolize) certain complex substances in the body. Without this enzyme, people cannot break down certain large sugar molecules. These molecules build up in the tissues, bones and major organs of the body. Eventually this damages the affected area and organs. Learn more.
[Batch Update 2016-09-20]