Chromosomal+Abnormalites

Germ Cell Mutations

Mutations that occur in gametes and can be passed on to offspring.

Somatic Cell Mutations

Mutations that occur in other cells and are not passed on to offspring.

Deletion

A type of mutation where a fragment breaks off and is lost.

Duplication

A type of mutation where a fragment breaks off and attaches to a homologous chromosome, giving it two copies.

Translocation

A type of mutation where a fragment breaks off and joins a non-homologous chromosome.

Inversion

A type of mutation where a fragment breaks off and reattaches backwards.

Karyotype

A photograph of chromosomes of an individual arranged by size and shape.

Amniocentesis

A procedure for extracting fetal amniotic fluid to collect cells with chromosomes for karyotyping.

Chorionic Villi Sampling

A procedure for extracting chorionic tissue to collect cells with chromosomes for karyotyping.

Autosomes

Chromosomes that are the same in male and female (chromosome pairs 1-22).

Sex Chromosomes

One pair of chromosomes that determines sex (chromosome pair 23).

Trisomy

A diploid cell with an extra chromosome.

Trisomy 21

Also known as Down Syndrome, characterized by having an extra chromosome 21.

Monosomy

A diploid cell missing a chromosome.

Turner’s Syndrome

A condition resulting from monosomy X, characterized by short stature and sterility.

Ploidy

An extra entire set of chromosomes; often results in heartier plants.

Nondisjunction

The failure of homologous chromosomes to separate during meiosis.