Genetic disorders are caused by changes in a person's genetic material, either inherited from their parents or acquired during their lifetime. These modifications can range from a single gene mutation to a serious chromosomal abnormality, and can affect any part of the body. The five most common genetic disorders are Down syndrome, Smith-Magenis syndrome, Prader-Willi syndrome, Angelman syndrome, and Fragile X syndrome. Down syndrome is the most commonly diagnosed chromosomal disorder, affecting 1 in 691 babies born in the United States.
It is caused by an abnormality in the parents that causes the disability to develop in the child. Symptoms of Down syndrome can range from tiny to severe, and include physical characteristics such as low muscle tone, short stature, and an upward slant to the eyes. Smith-Magenis syndrome is caused by the removal of genetic material from chromosome 17. It affects approximately 1 in 15,000 births and is characterized by common characteristics such as aggressive behavior, self-injury, sleep disturbances, and eating problems. Prader-Willi syndrome is caused by a deletion of genetic material from chromosome 15. It affects 1 in 10,000 to 30,000 people and is characterized by low muscle tone, short stature, cognitive disabilities, and an insatiable appetite that can lead to obesity.
Angelman syndrome is caused by a deletion of genetic material from chromosome 15. It affects 1 in 12,000 to 20,000 people and is characterized by developmental delays, speech impairment, seizures, and aggressive behavior. Fragile X syndrome is caused by a mutation of the FMR1 gene on the X chromosome. It affects 1 in 4,000 to 5,000 people and is characterized by intellectual disability, behavioral problems such as anxiety and hyperactivity, physical characteristics such as long face and large ears, and learning disabilities. If you or someone you know has been diagnosed with a genetic disorder, it's important to seek care from an experienced specialist. In addition to medical care for the disorder itself, genetic counseling can help families understand their risk for passing on the disorder to future generations.