Brainstorm…… Explain to the best of your ability what a
“genetic mutation” means to you……. (use all of your prior knowledge of biology!)
Crouzon Syndromegenetic disorder, skull bones fuse, 1-25,000 are
affected
More…..
And more….
Harlequin-type ichthyosis
Symptoms: Survival of about a month Skin is hard with thick scales Dehydration occurs quickly because the
skin can not maintain water Body temperature problems Difficulty breathing due to skin restriction
VERY GRAPHIC…
Neurofibromatosis
Neurofibromatosis The previous picture is of a 32 year old male
named Huang who lives in China Aprox. 50 lb. tumor Genetic disease that effects the development and
growth of nerve tissue Tumors may be removed but also very likely to
return Huang has currently had 2 surgeries to remove
his tumors
Tree Man – Human Papilloma Virus “Indonesia”
Dede after some treatment
Elastic Baby!Ehlers-Danlos Syndrome (genetic disorder of
connective tissue)
Genetic Mutations
A change in the DNA of an organism
Mutations 1. Germ cell mutation – mutations in gametes
(doesn’t affect organism) 2. Somatic mutations – mutation in an
organisms body cells, i.e. can affect the organism ex: human skin cancer, leukemia
3. Lethal mutations – cause death often before birth (some may form phenotypes that are beneficial natural selection)
Chromosomal Mutations(change in structure of chr. Or loss of entire chromosome
1. deletion: loss of piece of chr. (chr breakage) 2.inversion: chr. Segment breaks off and then
reattaches in reverse orientation to the same chromosome
3. translocation: chr. Piece breaks off and reattaches to another non homologous chr.
4. nondisjunction: failure of chr. To separate from its homologue during meiosis (when this occurs 1 gamete lacks the chr. entirely
CHROMOSOMAL DELETION !
CHROMOSOMAL INVERSION *
CHROMOSOMAL TRANSLOCATION
NONDISJUNCTION
*
Gene MutationsMay involve large segments of
DNA or a single nucleotide within a codon!
point mutation: substitution, addition, or removal of a single nucleotide
Point mutation(substitution)One nucleotide in a codon is replaced with a
different nucleotide resulting in a new codon
Sickle Cell Anemia(Point mutation) Substitutes adenine for thymine in a single
DNA codon Occurs in 1 in 500 African American in U.S Heterozygous generally healthy
Symptoms of Sickle Cell Anemia *
INSERTION & DELETIONMutations tend to be more
serious
Remaining codons after are all incorrectly grouped resulting in FRAME SHIFT MUTATION!
Frameshift Mutation