Lecture 17 - QF PCR Flashcards
What is aneuploidy
the gain or loss of a chromosome
What is monosomy
the loss of a chromosome
What is disomy
two copies of a chromosome
What is trisomy
three copies of a chromosome
What is non-disjunction
the failure of one or more pairs of homologous chromosomes to separate normally during nuclear division resulting in an abnormal distribution of chromosomes
What is turner syndrome
- 45 , X
- caused by paternal non-disjunction
What is the frequency of turner syndrome
1 in 2500 newborn girls
What is the phenotype of turner syndrome
-short stature
-webbed neck
-low hairline
-loss of ovarian function
-cardiac defects
-kidney disease
-normal intelligence
What is klinefelter syndrome
- 47, XXY
- caused by paternal and maternal non-disjunction
What is the phenotype of klinefelter syndrome
- tall with long limbs
- small testes and penis
- breast growth
- decrease sexual interest
- lower than average intellignece
what is the frequency of klinefelter syndrome
1/650 newborn boys in the US
1-2/1000 live male births in the UK
What is trisomy X
- 47, XXX
- caused by maternal non-disjunction
What is the phenotype of trisomy X
- taller than average
- developmental delays
What is the frequency of trisomy X
1/1000 female births in canada and the us
What is Jacob syndrome
- 47, XYY
- caused by paternal non-disjunction or post-zygotic cleavage errors