Because Down Syndrome is a genetic disorder, we can detect it through what is called a karyotype. A karyotype is basically a picture of a child's chromosomes which can be attained by taking a sample of the pregnant mother's amniotic fluid which contains that child's DNA. Down Syndrome, or trisomy 21, is the result of an extra copy of the 21st chromosome. Geneticists analyze a karyotype to determine whether or not a third copy of chromosome 21 is present and therefore, if the child will have Down Syndrome.
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