What is the rate of incidence for chromosomal disorders?

Honor Society of Nursing (STTI)

Some chromosomal disorders are more common than others. Scientists estimate that approximately one in every 200 babies is born with a chromosomal abnormality of one kind or another. Chromosomal abnormalities are also thought to be responsible for at least 50 percent of miscarriages that happen in the first trimester. Down syndrome is currently the most commonly occurring type of chromosomal disorder among live births.

Continue Learning about Chromosomal Disorders

National Down Syndrome Society

There are three types of Down syndrome: trisomy 21 (nondisjunction), translocation and mosaicism. ...

Dr. Jeanne Morrison, PhD

Chromosomal abnormalities are caused by errors in the number or structure of chromosomes. These erro...

National Down Syndrome Society

Students with Down syndrome are included in typical academic classrooms in schools across the countr...

Dr. Jeanne Morrison, PhD

There are many types of chromosomal disorders. The most common is Down syndrome, which is most oft...

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Chromosomal Disorders

The human body has 23 pairs of chromosomes: 22 pairs of autosomes and 1 pair of sex chromosomes. This gives humans 46 chromosomes in total. Every chromosome contains hundreds to thousands of your genes. Genes provide instructions for building proteins that help bodies grow and function properly. Chromosomal genetic disorders occur when chromosomes are partially or completely missing, altered or duplicated. An example of a chromosomal genetic disorder is Down syndrome. Down syndrome is the result of an extra, third copy of chromosome 21 being present in a person. This extra chromosome results in extra protein production and upsets the body’s balanced systems. During pregnancy chromosomal abnormalities can cause the death of an embryo or fetus. Chromosomal disorders can result in mental retardation or other developmental problems. Older pregnant women have a higher risk of passing on chromosomal genetic disorders.

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