1. Inheritance Patterns and Human Genetics Chapter 12-1 & 12-2

2. The sequence of A’s, T’s, G’s & C’s
tells the _______ of ________ in the ________
ORDER
amino acids
protein

3. Changes in the gene code _______________ that is made
A change in the genetic code =
________________
change the protein
MUTATION

4. KINDS OF MUTATIONS BODY SOMATIC ________ CELLS = ___________ CELLS
Somatic cell mutations can: ______________________
______________________
_____________
Cause cancer
Make cell not able to function
Kill cell
BUT _________ passed on to offspring
WON’T BE

5. Kinds of Mutations ___________ = _________cells (sperm & eggs) GAMETES
GERM
Germ cell mutations ________ passed on to offspring
CAN BE

6. MUTATIONS can be: HARMFUL
____________ - Mutations that produce ______________ are usually harmful.
Harmful mutations are associated with many
________________ and can cause
____________
defective proteins
genetic disorders
cancer

7. MUTATIONS can be: LETHAL ____________ - Some mutations
change proteins that are so vital to life that they cause death, usually before birth.
LETHAL

8. KINDS OF MUTATIONS Mutations that produce changes in a single gene =
_________________
in whole chromosomes = _____________________
GENE MUTATIONS
CHROMOSOMAL MUTATIONS

9. GENE MUTATIONS Mutations involving ________________
____________ = __________________ because they occur at a single point in the DNA sequence.
TYPES OF POINT MUTATIONS:
_____________________
One or a few
nucleotides
Point mutation
substitutions
deletions
insertions

10. SUBSTITUTION A T T C G A G C T A T T C T A G C T
Changes one base for another
A T T C G A G C T
A T T C T A G C T
How many amino acids get changed?

11. DELETION A T T C G A G C T A T T C A G C T
Piece of DNA code is lost
A T T C G A G C T
A T T C A G C T
How many amino acids get changed?

12. INSERTION A T T C G A G C T A T T C G C A G C T
Extra piece of DNA is added
A T T C G A G C T
A T T C G C A G C T
How many amino acids get changed?

13. GENE MUTATIONS
Substitutions usually affect no more than a single ____________, but deletions and insertions can have a more dramatic effect.
Amino acid
IMAGE FROM BIOLOGY by Miller and Levine; Prentice Hall Publishing©2006

14. FRAME SHIFT MUTATIONS Change multiple bases in code
thefatcatatetherat
____________________
INSERTION
thefatcataatetherat
DELETION
the fat cat ate the rat
the fat cat aat eth era t
the fat ata tet her at

15. FRAME SHIFTS
Frame shift mutations change every ___________ in the ___________ that follows the shift.
Frame shifts can alter a protein so much it is unable to _____________
Amino acid
protein
function

16. Location of the shift is important!
AT BEGINNING
the fat cat ate the rat
AT END
the fac ata tet her at
the fat cat ate thr at
MUTATIONS AT _____________OF GENE DAMAGE __________ OF THE CODE!
BEGINNING
MORE

17. CHROMOSOMAL MUTATIONS
Mutations involving changes in the _____________ or ______________
of whole chromosomes
TYPES OF CHROMOSOMAL MUTATIONS:
_____________________
Number
structure
deletions
duplications
inversions
translocations

18. DELETION Piece of chromosome is lost
________________________________________

19. DUPLICATION Piece of DNA is copied too many times
________________________________________________

20. INVERSION
Segment flips and reads backwards

21. TRANSLOCATION
Segment breaks off and joins a different non-homologous chromosome

22. POLYPLOIDY
Condition in which an organism has extra sets of chromosomes
= _______________
__________ in humans, but beneficial
in some ___________.
POLYPLOIDY
LETHAL
plants

23. PHENYLKETONURIA (PKU)
A mutation that causes a protein to be
NON-FUNCTIONAL would appear
_______________ to the normal working allele.
Examples of __________________________ GENETIC DISORDERS:
____________________
RECESSIVE
AUTOSOMAL RECESSIVE
PHENYLKETONURIA (PKU)
TAY-SACHS DISEASE
CYSTIC FIBROSIS

24. Phenylketonuria (PKU)
CAUSE: Mutation in gene for an ___________ that __________ an ___________ called phenylalanine
Build up causes ________________________
ENZYME
breaks down
amino acid X X
MENTAL RETARDATION

25. TAY-SACHS DISEASE ___________________
AUTOSOMAL RECESSIVE
CAUSE: Mutation in gene for an ___________ that breaks down a kind of _________in the developing _________
Build up of lipids in brain cells leads to: mental retardation, blindness, and DEATH in early childhood
ENZYME
LIPID
BRAIN

26. CARRIER heterozygous A __________ person who carries a
_________ allele for a
genetic disorder, but
______________ the
disorder themselves
is called a
_____________
heterozygous
recessive
doesn’t show
CARRIER

27. CYSTIC FIBROSIS protein Cl- ions thick mucous
CAUSE: Loss of 3 DNA bases in a gene for the _____________ that transports _________ so salt balance is upset
Causes a build up of _________________ in lungs and digestive organs .
protein
Cl- ions
thick mucous
Image from: BIOLOGY by Miller and Levine; Prentice Hall Publishing ©2006

28. CYSTIC FIBROSIS

29. CYSTIC FIBROSIS
Leads to:
_________ and _________ complications, increased susceptibility to infections;
“__________” is a symptom
30,000 people in U.S. have cystic fibrosis
1 in 31 people are carriers
respiratory
digestive
Salty skin

30. DOMINANT AUTOSOMAL DOMINANT Huntington’s disease Achondroplasia
A mutation that codes for a new protein
whose action masks the normal allele
appears as a ______________ mutation.
Examples of _________________________ GENETIC DISORDERS:
____________________
DOMINANT
AUTOSOMAL DOMINANT
Huntington’s disease
Achondroplasia

31. HUNTINGTON’S DISEASE ______________________
AUTOSOMAL DOMINANT
CAUSE: Extra ______________ at end of gene on chromosome 4
The _____________ the more __________ the symptoms.
CAG repeats
more repeats
severe

32. HUNTINGTON’S DISEASE loss
Huntington’s brain
loss
Causes progressive _____ of ________________ and ___________function
muscle control
mental
1 in 10,000 people in U.S.
have Huntington’s disease
Normal brain

33. A person with
Huntington’s disease
has a _____ chance of
passing the disorder on to
their offspring.
50%
Problem: Symptoms of disorder usually don’t show until ____________ . . .
so you don’t know you have it until ________ you have had children.
MIDDLE AGE
AFTER

34. ACHONDROPLASIA (One kind of Dwarfism)
AUTOSOMAL DOMINANT
CAUSE: ___________________________ gene
1 in 20,000 births

35. ACHONDROPLASIA (One kind of Dwarfism)
Normal size head and torso; short arms and legs
Problem with way cartilage changes to bone as bones grow

36. BY ____________________
DISORDERS CAUSED
BY ____________________
____________________
AUTOSOMAL CODOMINANT ALLELES
SICKLE CELL DISEASE
CAUSE: A changed to T in gene for
__________________
(protein in red blood cells
that carries oxygen in blood)
HEMOGLOBIN

37. SICKLE CELL DISEASE SYMPTOMS:
_____________ become sickle shaped in persons with ______
sickle cell ________
RED BLOOD CELLS
TWO
ALLELES

38. HOMOZYGOUS sickle cell sickle disease HOMOZYGOUS malaria HETEROZYGOUS
A person who is __________________ for the ____________allele (ss) will have _______________
A person who is _________________ for normal hemoglobin alleles will have normal blood cells, but can become infected with __________ (SS)
A _________________ person (Ss)
(with one normal/one sickle cell allele) is
generally healthy and has the benefit of
being _________ to malaria
sickle cell
sickle disease
HOMOZYGOUS
malaria
HETEROZYGOUS
resistant

39. Chromosomes that determine the sex of an organism = _________________
All other chromosomes = _________________
Sex chromosomes
autosomes
Humans have two sex chromosomes
and _____ autosomes X y 44

40. SEX DETERMINATION
XX =
female
Xy =
male

41. Who decides? X X Mom can give X X Dad can give X or y y X X X X X y
SO ____ determines sex of the baby.
If dad gives X with mom’s X = girl
If dad give y with mom’s X = boy

42. PEDIGREES
_______________are diagrams that show how are ____________ on __________ over several generations
genes are passed
in families

43. Drawing a pedigree chart

45. SEX CHROMOSOMES CAN CARRY OTHER GENES TOO = ___________________
SEX LINKED TRAITS
These traits show up in different
_______________ in males and females
because they move with the sex chromosomes
percentages

46. EXAMPLE: Hairy pinna Y linked in males Y-LINKED GENES:
Genes ______________ chromosome
carried on Y
EXAMPLE: Hairy pinna
ONLY
Y linked
in males
_________genes _____ show up _______

47. are carried on the X chromosome
X-LINKED
____________ GENES:
are carried on the X chromosome
X-linked recessive disorders
show up _____________
in ______ than females
because males only have
______ X chromosome.
MORE frequently
MALES
ONE

48. Or Males ONLY HAVE ONE X They either have the They are disorder normal
DEFECTIVE
NORMAL
They either
have the
disorder
They are
normal Or

49. Females have one normal gene that works.
FEMALES HAVE TWO X CHROMOSOMES
DEFECTIVE
NORMAL
DEFECTIVE
Females have one normal gene that works.
Females __________ defective recessive
alleles to show the
disorder
need 2

50. X-LINKED RECESSIVE
Examples of ________________________ DISORDERS:
____________________
HEMOPHILIA
COLORBLINDNESS
DUCHENNE MUSCULAR DYSTROPHY

51. HEMOPHILIA Blood clotting proteins on X bleed to death
CAUSE: Mutation in genes for __________________ carried ______ chromosome
Blood clotting proteins are missing so person with this disorder can’t stop bleeding when injured; can ________________ from minor cuts or suffer internal bleeding
from bruises or bumps.
Blood clotting proteins
on X
bleed to death

52. COLORBLINDNESS Color vision Red-green
CAUSE: Mutation in one of three genes for _______________ carried on X chromosome
Persons with this disorder have trouble distinguishing colors.
_________________
colorblindness is most common
Seen in 1 in 10 males
1 in 100 females
Color vision
Red-green

53. ________ traits show up _______ in _______ __________________ traits:
What’s the pattern:
________ traits show up _______ in _______
__________________ traits:
______________________ than females.
________________ can be ________.
_______________________ traits:
BOTH ______ & _________ can be ________
Y-linked ONLY males
X-linked recessive
more common in males
ONLY FEMALES carriers
AUTOSOMAL RECESSIVE
MALES FEMALES carriers

54. ____________________________: Change in the ______________ or
CHROMOSOMAL MUTATIONS
____________________________:
Change in the ______________ or
____________ of chromosomes
structure
number

55. Homologous chromosomes ________________ during MEIOSIS
= _________________________
One cell gets 2 copies of
the chromosome the
other cell gets none.
fail to separate
NONDISJUNCTION

56. Nondisjunction

57. Nondisjunction Since it happens to a sperm or egg, the new
baby can end up
with _____________ of a
chromosome
= __________________ OR
only ___________ of a
= ___________________
3 copies
TRISOMY
one copy
MONOSOMY

58. Down syndrome (= ____________)
TRISOMY 21

59. Down syndrome (Trisomy 21)
1 in 800 births
Similar facial features
Slanted eyes
Protruding tongue

60. Down syndrome (Trisomy 21)
Most common chromosomal abnormality
50% have heart defects that need surgery to repair
Mild to severe mental retardation
Increases susceptibility to many diseases
Risk of having a child with Down syndrome increases with age of mom

61. Klinefelter syndrome 1 in 1000 births Males have extra X chromosomes
(Can be XXy, XXXy, or XXXXy)
Average to slight decrease in intelligence
Small testes/can’t have children
Usually not discovered until puberty when don’t mature like peers