Chromosomal Abnormalities Flashcards
Types of Chromosomal Abnormalities
Numerical
Structural
Abnormality where this additional number of chromosome
Numerical Chromosomal Abnormality
Abnormality where the chromosome pair may have a missing or redundant part of a gene
Structural Chromosomal Abnormality
The usual number and sets of chromosomes
Euploidy
Th presence of 3 or more complete sets of chromosomes
Polyploidy
The presence of additional chromosomes or missing individual chromosomes
Aneuploidy
Refers to the number of sets of chromosomes in a cell or an organism
Ploidy
Malsegregation of the chromosomes during division
Nondisjunction
Abnormal separation or the failure of separation of the chromosome that will result into abnormal chromosome numbers
Nondisjunction
Types of Polyploidy
Triploidy
Tetraploidy
Type of Polyploidy:
3 sets of chromosomes (23 x 3) (69 chromosomes)
Triploidy
Type of Polyploidy:
4 sets of chromosomes (23 x 4) (92 chromosomes)
Tetraploidy
Types of Euploidy
Monosomy
Trisomy
Type of Euploidy:
One less chromosome (45 chromosomes)
Monosomy
Type of Euploidy:
One additional chromosome (47 chromosomes)
Trisomy
Examples of syndromes when Aneuploidy Occurs
Patau Syndrome (Trisomy 13)
Edwards Syndrome (Trisomy 18)
Down Syndrome (Trisomy 21)
Turner Syndrome
Klinefelter Syndrome (XXY)
Jacob’s Syndrome (XYY)
Trisomy 21 is aka?
Down Syndrome
An example of Chromosomal Aberration
Trisomy 21 (An extra chromosome on the 21st chromosome)
Trisomy 18 is aka?
Edward’s Syndrome
Average life span of infant with Edward’s Syndrome
2-4 months
Trisomy with highest mortality
Trisomy 13
Trisomy 13 is aka?
Patau Syndrome
Most aborted infant Triosomy disorder
Trisomy 13
Average lifespan of infants with Patau Syndrome
6 months
Having one fewer chromosome in each body cell
Monosomy
Example of Monosomy
Turner’s Syndrome
Syndrome where there is only one sex chromosome (Only X)
Turner’s Syndrome
Types of Sex-Linked Trisomy
Klinefelter Syndrome
Jacob’s Syndrome
Disorder where there is nondisjunction of the X chromosome; Males have an extra X chromosome (XXY)
Klinefelter Syndrome
Infertility in Klinefelter Syndrome results from?
Azoospermia
Complete absence of sperm
Azoospermia
“Super Male” syndrome; There is an extra Y chromosome (XYY)
Jacob’s Syndrome
Shorthand of Down Syndrome
47, XX/XY, +21
Incidence of Down Syndrome
1/750-800
Shorthand of Edward Syndrome
47, XX/XY, +18
Incidence of Edward Syndrome
1/6,000-11,000
Shorthand of Patau Syndrome
47, XX, +13
Incidence of Patau Syndrome
1/15,000
Incidence of Turner Syndrome
1/5,000
Shorthand of Klinefelter Syndrome
46, XXY
Shorthand of Jacobs Syndrome
47, XYY
