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21 Cards in this Set

  • Front
  • Back
Down's Syndrome Cytology
Trisomy 21 (95%)
Translocation (3%)
Mosaic (2%)
Edward's Syndrome Cytology
Trisomy 18 (most)
Translocation and Mosaic (rare)
Patau's Syndrome Cytology
Trisomy 13 (most)
Translocation (not uncommon)
Mosaic (rare)
Klinefelter's Syndrome Cytology
47, XXY (80%)
Mosaic (46,XY/47,XXY)
48,XXXY (rare)
49,XXXXY (very rare)
Double-Y Cytology
47, XYY (most)
48,XXYY (very rare)
Turner's Syndrome Cytology
45,XO (50-60%)
Mosaic (46,XX/45,XO)
Deletions (46,XX,Xp or 46,XX,Xq)
Superfemale Cytology
47,XXX (most common)
48,XXXX (rare)
49,XXXXX (rare)
Down's Syndrome Incidence
1/800 Live Births

*Maternal Age Effect (as mentioned 4,327 times in lectures):

<25 years: 1/1600
35 years: 1/350
40 years: 1/100
>45 years: 1/25
Edward's Syndrome Incidence
1/8000 (80% are female)

*Maternal Age Effect
*High fetal mortality
Patau's Syndrome Incidence

*Maternal Age Effect
*Males and females equally affected
Klinefelter's Syndrome Incidence
1/1,000 male births

*Weak Maternal Age Effect
Double Y Incidence
1/1,000 male births

*Unknown Maternal Age Effect?
Turner's Syndrome Incidence
1/5,000 female births

*rare due to spontaneous abortions
Superfemale Incidence
1/1,000 female births

*Maternal Age Effect
Down's Syndrome Abnormalities
*Short stature
*Small hands/feet
*Broad face/neck
*Flat occiput
*Small ears
*Protruding tongue
*Slanting eyes (mongolism)
*Mental retardation
*Prone to infection
*Male infertility
Edward's Syndrome Abnormalities
*Failure to thrive
*Hypertonicity, clenched fingers
*Prominent occiput
*Low set, malformed ears
*Small chin
*Short sternum
*Small pelvis
*Rocker-bottom feet
*Heart defects
*Profound mental retardation

**Most die within one year
Patau's Syndrome Abnormalities
*Sloping forehead
*Forebrain defects
*Eye abnormalities
*Cleft lip and palate
*Low set, malformed ears
*Heart defects
*Profound mental retardation

**Most die within one year
Klinefelter's Syndrome Abnormalities
*Small testicles
*Long legs
*Poor development of secondary sexual characteristics
*Reduced IQ
*Low testosterone, estrogen variable
*High pituitary gonadotropins (due to reduced androgens)
Double Y Abnormalities

*Increased height
*Reduced IQ
*Increased delinquency
Turner's Syndrome Abnormalities
At birth:

*Peripheral lymphedema affecting dorsum of hands and feet and sides of neck

During childhood:

*Short stature
*Webbing of neck
*Broad chest
*Widely spaced nipples
*Low posterior hairline
*Cubitus valgus (high angle at elbow)
*Aortic coarctation (narrowing)

At puberty

*NO puberty
*Ovaries degenerated (due to accelerated follicular atresia)
*Normal intelligence
*Low estrogen, high pituitary gonadotropins (trying to stimulate ovarian estrogen production)
Superfemale Abnormalities
NO consistent abnormalities (sometimes mild mental deficiency or dysmorphic features)

*More severe abnormalities in females with 4 or 5 X chromosomes