Chromosome Abnormalities and Aneuploidy

Flashcards about chromosomes, karyotypes, and aneuploidy

Karyotype

A display of chromosome pairs ordered by size and centromere location, used to look for abnormalities in chromosome number or structure.

SRY gene

A gene on the Y chromosome that codes for the development of testes.

Autosomal Chromosomes

The 22 pairs of chromosomes that are not sex chromosomes.

Aneuploidy

Change in chromosome number, resulting from nondisjunction.

Nondisjunction

Failure of chromosomes to separate during meiosis.

Monosomy

Having only one copy of a chromosome instead of the usual two.

Trisomy

Having three copies of a chromosome instead of the usual two.

Down Syndrome

Trisomy 21, a condition caused by an extra copy of chromosome 21.

Which of the meiosis is more serious for nondisjunction event?

It's much more serious if you have that nondisjunction event in meiosis one because none of the gametes will be normal.

Turner Syndrome

Condition where a female has only one X chromosome (XO).

Klinefelter Syndrome

Condition where a male is born with one or more extra X chromosomes (e.g., XXY).