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HUMAN GENETICS
Some mutations result in genetic disorders in
human --- sickle cell anemia and cystic fibrosis
both resulted from changes in DNA
Recessive genetic disorders - 1000 known
recessive disorders in humans
Person with single copy of gene---> carries trait
Person with 2 copies of gene ---> has disorder
HUMAN GENETICS - - SICKLE CELL
Red blood cells are
misshapen due to
hemoglobin molecule not
normal
Cannot carry oxygen to
body cells
Don’t move thru blood
vessels easily
Commonly found in tropics
Helped by drugs and
transfusions
HUMAN GENETICS - cystic fibrosis
A homozygous recessive disorder
Thick mucus build up in lungs & intestines
Difficulty breathing - causes lung damage
Digestive tract - damages pancreas
Occurs in Caucasians - 1/20 is a carrier
Helped with antibiotics,diet, physical
therapy
HUMAN GENETICS -SEX DETERMINATION
Females have XX
chromosomes in
cells
Males have XY
chromosomes in
cells
Sex of offspring is
determined by the
male parent
HUMAN GENETICS -
SEX LINKED DISORDERS
sex linked gene = an allele inherited on a sex chromo
Color blindness -
Normal vision XX or
XY
Carrier XX*
Color blind X*Y
Also - hemophilia
Importance of genetics
Gain information about genetic and sexlinked disorders
Genetic engineering Improve crop production
Produce medications - insulin
Change how cells perform normal
functions - bacteria that break down oil
Eventually to correct human genetic
disorders
HUMAN GENOME PROJECT
AIM - to sequence all DNA on all 43
human chromosomes
Genome - a map of the location of
individual genes on every chromosome in
an organism
Humans - 46 chromosomes with more than
75,000 genes in each body cell
Genome info may help pinpoint specific
disorders - diagnosis, screening,gene therepy