Transcript 7-3 Genetic Disorders

7-3 Genetic Disorders
Vocabulary
and
Graphic Organizers
A change in a gene. In
some cases, genes are
sometimes damaged
or copied incorrectly.
The mutation will only
be expressed if both
parents pass on the
recessive gene.
Mutation
Most mutations are
recessive and are not
expressed in the
heterozygous condition
Harmful mutations
can cause genetic
disorders
Harmful effects that
are produced by
mutations
Sickle cell anemia
Hemophilia
In most cases genetic
disorders are recessive
Genetic
disorder
Down syndrome
Cystic fibrosis
Gene Therapy
Recessive genetic
disorder caused by a
mutation in a gene
that codes for a
transport protein
Cystic
fibrosis
In the homozygous condition
– causes cells in respiratory
and digestive systems to
produce misshapen transport
proteins
Researchers have
located the gene that
causes Cystic fibrosis.
Patients have trouble
breathing and digesting
their food
Mucus forms in the
lung and pancreas
Healthy copy of the
mutated gene is
transferred into the
lungs of cystic fibrosis
patients
The possibility is still in the
stages of research
Gene
Therapy
This could be a
potential cure in the
near future
Recessive gene
disorder caused by
mutation in the gene
that codes for
hemoglobin
Hemoglobin is the protein in
red blood cells that moves
oxygen throughout the body
Sickle cell
anemia
Heterozygous
condition is resistant
to Malaria
Causes low blood
iron, fatigue,
headaches, muscle
cramps
Hemophilia
Recessive genetic
disorder caused by a
mutation on the
X chromosome
Causes the body to build a
defective form of a protein
needed to clot blood
Sex-linked
inheritance
Carried on the X
chromosome. Women
are carriers, while men
will develop the disorder
Small cuts are
difficult to heal and
internal bleeding
could be fatal
Sex-linked
inheritance
Traits that are
determined by genes
located on the X
chromosome
Arises from 3 copies
of chromosome 21
Down
syndrome
Physical characteristics:
Extra folds in upper
eyelids, broad and
flattened nose, thick
tongue, and mental
retardation
Occurs in about 1 of
every 1000 births
Genetic Counseling and
Gene Therapy If one member of the family has
Carrier
a genetic disorder, it is possible
that other members of the
family have the recessive gene.
Person who is heterozygous for
recessive mutation. They are
known as a carrier of the gene.
Genetic
Counseling
Kids –
to have, or
not to have
pedigree
A Genetic counselor will look for a
pattern in the family history of genetic
disorders to try and determine whether
the client is at risk of having children
with a genetic disorder
A pedigree is a record that
shows inheritance patterns over
several generations
Genetic
Counseling