Chromosomal Abnormalities and Associated Syndromes

Trisomy 21

Down Syndrome, a chromosomal abnormality in which an individual has 3 copies of chromosome number 21.

Extra chromosomes

Means that there is excess genetic information and an unpaired chromosome in every cell.

Trisomy 18

Edwards Syndrome, approximately 1 in 6000 live births, characterized by many organ system defects and a low survival rate, with most fetuses dying before birth.

Trisomy 13

Patau Syndrome, approximately 1 in 25,000 births, involving three copies of chromosomes found in chromosome 13, leading to severe developmental issues and kidney and heart defects, with a very low survival rate.

XXY

Klinefelter's Syndrome, characterized by two X and one Y sex chromosome, approximately 1 in 500 male births, where males are usually sterile and exhibit some feminine characteristics.

Monosomy X

Turner syndrome, where only 1 X chromosome is found in the 23 chromosomes, occurring in approximately 1 in 2500 female births, resulting in a female appearance that may mature, but they may not receive their menstrual cycle and are sterile.