Individual who has one copy of the allele for a recessive disorder and does not exhibit symptoms.
Change to a chromosome in which a fragment of the chromosome is removed.
General set of symptoms in people with Trisomy 21.
Change to a chromosome in which part of the chromosome is repeated
Change to a chromosome in which a fragment of the original chromosome is reversed.
Event during meiosis in which homologous chromosomes or sister chromatids fail to separate.
Family tree that records and traces the occurence of a trait in a family.
Change to a chromosome in which a fragment of one chromosome attaches to a nonhomologous chromosome.
Condition in which an individual has three numer 21 chromosomes, resulting in Down Syndrome.