Difference Between Down Syndrome And Disease
Down syndrome, formerly called Down’s syndrome, is a chromosomal disorder that causes a distinct set of physical and mental characteristics in affected people. Physical characteristics may include slightly slanted eyelids, a flattened nasal bridge, short stature, and overall slower maturation than their peers. There is a wide variation in the mental ability of people with Down syndrome, but most are mildly to moderately retarded.
People with Down syndrome have an extra chromosome 21. This is believed to develop during germ cell formation, when the two number 21 chromosomes do not separate properly. At conception the affected ovum or sperm unites with a normal germ cell, and the resulting embryo has 47 chromosomes instead of the typical 46. This condition, known as trisomy 21, occurs in about 95% of persons with Down syndrome (see genetic diseases). There are two other variants of Down syndrome. Translocation occurs in 3–4% of persons with Down syndrome, when a partial number 21 chromosome is attached or translocated to another chromosome. In mosaic Down syndrome some cells have 47 chromosomes and some have 46; this is found in about 1% of persons with Down syndrome.
The risk of having a child with Down syndrome increases with maternal age. The syndrome is detectable in a fetus by amniocentesis and other forms of prenatal testing. About one out of every 800–1,000 babies born in the United States has Down syndrome, and of those, approximately 40–50% are born with heart defects and 8–10% have gastrointestinal anomalies. Most of these physical problems are surgically correctable.
Loving homes, good medical care, early intervention, and inclusion in all aspects of society lead to high quality of life and a long life expectancy for persons with Down syndrome.
A disease is a disturbance of a body structure or function. It may make a person physically or mentally ill, limit his or her activities, or even lead to death. Sometimes disease brings obvious changes in body structures, such as swelling of the jaw in mumps or the open sores in certain types of cancer. Sometimes no changes in body structures can be found, even under a microscope, but the person loses some normal capabilities—cannot see clearly, for example, or is unable to become pregnant.
Subjective changes—things that the sick person feels, such as pain or weakness—are called symptoms of disease. Objective changes, which other people can observe, are referred to as signs of disease. Unusual redness or a spotty rash on the skin, a higher than normal body temperature, an increase in the number of white blood cells, and various other changes that can be seen or discovered through tests can all be signs of disease.