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thehappyhospitalist.blogspot.com/2008_10_01_a...
Genetic Traits ?
http://www.telegraph.co.uk/news/worldnews/asia/indonesia/tree-man/
Dominant and Recessive Traits
Dominant traits
are seen in the
phenotype
for both
Heterozygous (Tt)
and
Homozygous (TT)
genotypes.
Dominant Examples:
• Tongue-roller
• Freckles
• High blood pressure
• Dwarfism
• Six fingers
• Baldness (males)
• Dimples
Recessive traits are seen in the phenotype ONLY
When a person has a Homozygous (tt) genotype.
Genetic Diseases
Dominant (TT or Tt)
• Huntington’s
Recessive (tt)
• Tay-Sachs
• PKU
• Cystic Fibrosis
• Sickle-cell Anemia
Sex-Linked Recessive
(XrY) or (Xr Xr)
• Hemophilia
• Color blindness
Other Inherited Diseases
Down Syndrome
(3 copies of chromosome 21)
Nondisjunction
Examples of Diseases
which are NOT Inherited
Cancer
• Some cancers are due
MOSTLY to environmental
exposure
• Some cancers have a
genetic risk factor
Infectious Diseases
• Chickenpox
• Flu
• Strep throat
• Food poisoning
Diet
• Some diseases are caused by a lack of nutrients
like vitamin C