Download Human Genetic Disorders

Human Genetic
Disorders
Mrs. Wharton’s Science Class
What is Genetic
Disorder?



A genetic disorder is an abnormal
condition that a person inherits
through genes or chromosomes.
Some genetic disorders are caused by
mutations in the DNA of genes
Other disorders are caused by changes
in the overall structure or number of
chromosomes.
Cystic Fibrosis



Occurs when the body produces an
abnormally thick mucus in the lungs
and in the intestines. It makes it hard
to breathe and digest food.
Caused by a recessive allele
There is no cure but there are
treatments to help control the
symptoms
Sickle Cell Disease




Affects the hemoglobin , the protein in the
blood that carries oxygen
People with sickle cell suffer from lack of
oxygen in the blood and experience pain
and weakness
The allele that carries sickle cell is
codominant with the normal allele.
There is no cure but there are medications
to lesson the pain and other symtoms.
Hemophilia




When the blood clots very slowly or not at
all.
People with this disorder do not produce
one of the proteins needed for blood to clot
normally
Caused by a recessive allele on the X
chromosome therefore occurs more often in
males
With treatment people with hemophilia can
lead normal lives
Down Syndrome




A genetic disorder when there is an extra
copy of chromosome 21
Occurs when a chromosome fails to
separate correctly during meiosis
People with down syndrome have distinctive
physical appearance and some mental
retardation.
Many people with down syndrome lead
normal active lives.
Studying Family Trees




Geneticist- one who studies genetics
Pedigree- a tool a geneticist uses to follow
the passing of certain traits from generation
to generation.
Karyotype- picture of all of the
chromosomes.
Genetic counselor- a person who uses
pedigrees, punnett squares, and karyotypes
to determine the likelihood of a certain trait
or genetic disorder to be passed on from
generation to generation.