Down Syndrome (trisomy 21) result of an extra chromosome 21 1:700 children characteristic facial features, short stature; heart defects, shorter lifespan… etc. has been correlated to the age of the mother but can also be result of nondisjunction of father’s chromosome 21

Down Syndrome

Patau Syndrome (trisomy 13) serious eye, brain, circulatory defects as well as cleft palate 1:5000 children rarely live more than a few months

Klinefelter syndrome: XXY 47 chromosomes affects the sexual/gender specific characteristics Usually male sex organs with other female body characteristics Normal intelligence

Jacob’s Syndrome XYY males individuals taller than average, often with below normal intelligence

Trisomy X XXX metafemales 1:1000 live births healthy and fertile usually cannot be distinguished from normal female except by karyotype

Monosomy X – Turner’s Syndrome Only one sex chromosome – X 1:5000 Only monosomy that will produce viable offspring in humans Only have 45 chromosomes Do not mature sexually during puberty and are sterile (cannot reproduce) Short stature and normal intelligence 98% of these fetuses die