1. Chapter 12 Review Inheritance Patterns and Human Genetics
Mutations and Genetic Disorders

2. Chapter 12 Handouts to Study
Vocabulary quiz
“Chapter 12 Notes” – Inheritance Patterns and Human Genetics (picture of karyotype on front)
“ Ch 12 Human Genetics Part 2” (picture of pedigree on front)
Problem Set: Sex-linked genes and Multiple Alleles ( Punnett Square problems)
Powerpoint Handout
Human Face Lab (patterns of inheritance: Complete Dominance, Incomplete Dominance, Polygenic, Epistasis)
Pedigree Practice
Genetic Disorders

3. Mutations
DNA mutations Point (single nucleotide). Several types: when one nucleotide replaces another Sometimes can be “silent” (no amino acids are changed. Sometimes causes problem—one amino is changed but that can cause a change in the whole protein.
Substitution

4. DNA Mutations (cont’d)
When one nucleotide is added
When one nucleotide is removed.
Both result in
Insertion
Deletion
Frameshift Mutations

5. Chromosome Mutations
Pieces of chromosomes break off and move. Deletion,Inversion,Translocation
Inversion
Translocation
Deletion

6. The person in this picture is a male female
This organized picture of an individual’s chromosomes is called a __________________
karyotype
The person in this picture is a
male female
Female
There are 2 X and no y chromosomes.

9. Prader-Willi Syndrome Deletion on chromosome 15
Name ,Chromosome
Incidence
Characteristicsa
Down Syndrome, 47, Trisomy 21
1 per ,000 births
Protruding tongue, thick lips, flat nose, short neck, wide gaps between toes, short fingers, heart problems and hearing loss. Mental retardation can range from mild to severe. Children often have good visual discrimination skills and may be better at understanding verbal language than producing it.
Klinefelter Syndrome
47, XXY
1 per ,000 boys
Diagnosis may not occur until adolescence, when testes fail to enlarge. Affected boys tend to have long legs, to grow modest breast tissue, a/1d to remain sterile. They tend to show lower than average verbal ability and some speech and language delays.
Turner Syndrome
45, X_
1 per 2, ,000 girls
Affected girls have broad chests, webbed necks, short stature, and specific health problems. They do not show normal sexual development. They may show normal verbal ability but lower than average ability in processing visual and spatial information.
Prader-Willi Syndrome
Deletion on chromosome 15
1 per 10, ,000 births
Children with this syndrome tend to become obese and show mental retardation; they also have small hands and feet and are short in stature.
Cri-du-Chat syndrome
Deletion on chromosome 5
1 per 20, ,000 births
“Cry of the cat” referring to the distinctive cry of children due to abnormal larynx development, Babies are usually small at birth, may have respiratory problems; may have a small head (microcephaly), an unusually round face, a small chin, widely set eyes, folds of skin over their eyes, and a small bridge of the nose. Some have heart defects, muscular or skeletal problems, hearing or sight problems, or poor muscle tone, difficulty walking and talking.
Williams Syndrome
Deletion on Chromosome 7
1 per 10,000 births
Intellectual disability, heart defects, unusual facial features (small upturned nose, wide mouth, full lips, small chin, widely spaced teeth). failure to gain weight appropriately, kidney abnormalities, and low muscle tone.
Patau Syndrome 47, Trisomy 13
1 per 16,000 births
Cleft lip or palate, Clenched hands, Close-set eyes -- eyes may actually fuse together into one), Decreased muscle tone, Extra fingers or toes (polydactyly), Low-set ears
Intellectual disability (severe), Seizures, Skeletal (limb) abnormalities, Small eyes, Small head (microcephaly) More than 80% of children with trisomy 13 die in the first year.
Edwards Syndrome 47, Trisomy 18
1 per 6,000 births
Heart defects, Kidney problems, Part of the intestinal tract is outside the stomach (omphalocele), The esophagus doesn’t connect to the stomach (esophageal artesia), Clenched hands, Delayed growth Small jaw (mycrognathia)
Small head (microcephaly) Low-set ears. Severe developmental delays. High mortality rate first year.
Jacobs Syndrome 47, XYY
1 per 1,000 male births
Affected individuals are usually very tall. Many experience severe acne during adolescence. May have learning disabilities and behavioral problems such as impulsivity. Intelligence is usually in the normal range, although IQ is on average points lower than siblings.
XXX Syndrome
47, XXX
1 per 1,000 female births
Taller than average, normal sexual development, able to conceive, increased risk of learning disabilities, delayed speech, motor skills, weak muscle tone, behavioral and emotional difficulties, Seizures or kidney abnormalities .

10. Name an X-linked genetic disorder.
The genetic disorder in which the person can’t make the protein needed to make their blood clot is called ______________________
hemophilia
Name an X-linked genetic disorder.
Hemophilia, colorblindness, Muscular dystrophy

11. A person with trisomy-21 (three #21 chromosomes) has ____________
Genetic disorder in which a person can NOT
breakdown phenylalanine and eating foods containing this amino acid causes them to become retarded.
_________________
Phenylketonuria (PKU)
A person with trisomy-21 (three #21 chromosomes) has ____________
Down syndrome

12. The cell that forms when an egg and a sperm
join together is called a _______________
zygote
TRUE or FALSE
GERM cell mutations can be passed on to
offspring.
TRUE : Germ cells are reproductive cells. Changes in the DNA of these cells is passed on to the offspring.

13. An autosomal trait is found on the X chromosome
A trait that is controlled by several genes
(like skin color or height) is called ______________
polygenic
TRUE or FALSE
An autosomal trait is found on the X chromosome
FALSE Autosomes are the chromosomes that are NOT sex chromosomes.

14. What type of disease? Autosomal dominant
Huntington’s disease is a genetic disease that causes a deterioration of brain tissue by middle age, sometimes after it has been passedto a person’s offspring.
It is a mutation on chromosome 4. It shows up in both males and females. It shows up even when only one chromosome is defective. (HH or Hh).
What type of disease?
Autosomal dominant

15. Eye color is a _____________ trait.
A trait in which there are three or more choices
for a single gene (like A, B, and O blood type) is a ____________ trait.
polygenic multiple allele
Multiple allele
Eye color is a _____________ trait.
Polygenic Multiple allele sex linked
polygenic

16. ______________ mutations cause death often before birth.
A body cell is also called a ______________ cell.
SOMATIC
______________ mutations cause death often before birth.
LETHAL

17. A person with the Xy genotype would be
male female
male
A _________ cell mutation happens in sperm or egg cells.
GERM

18. Twins that come from one sperm and egg are called _____________
MONOZYGOTIC or Identical
Which person shows that they
have the trait (visible in their
Phenotype)? A B A C

19. X-linked genes _______________
This picture shows a ___________________
Karyotype
Pedigree
Punnett square
pedigree
X-linked genes _______________
Only show up in females
Show up more frequently in males
can be heterozygous in males
only pass from mothers to daughters
Show up more frequently in males

20. Which type of mutation can be passed along to offspring?
Somatic cell mutation Germ cell mutation
Germ cell mutation
When homologous chromosomes don’t separate
during meiosis it is called _________________
nondisjunction

21. Which parent determines the sex of the baby?
father
What is the difference between a germ cell mutation and a somatic cell mutation?
Somatic cells are body cells and mutations in these cells are NOT passed on to offspring.
Germ cells are reproductive cells. Mutations in these cells CAN be passed on to offspring.

22. Females can be carriers for X linked genes
TRUE or FALSE
Females can be carriers for X linked genes
TRUE
Why do X-linked recessive disorders show up
more in males than females?
Males only have one X. If they get the gene it will show.
Females have a 2nd X that can “hide” the disorder gene. They need 2 copies of the gene to show disorder. Males don’t have a “back up” X.

23. What disorder is it? Hemophilia Sickle cell anemia
Mutation in the blood clotting protein makes
person unable to stop bleeding after an injury _______________
Mutation in hemoglobin causes red blood
cells to change shape and ____________________
clog up blood vessels
Mutation causes mental retardation
if foods containing phenylalanine are eaten _____________________
Three #21 chromosomes are present
causing mental retardation _______________________
Mutation in ion channel protein causes thick mucous to clog up lungs and digestive organs _______________________
Hemophilia
Sickle cell anemia
Phenylketonuria (PKU)
Down syndrome
Cystic fibrosis

24. What disorder is it? Huntington’s disease (HD)
Gradual deterioration of the brain that appears during middle age resulting
in nursing home care and early death ____________________
Progressive weakening of muscle proteins resulting in inability to walk and eventually death _________________________
Inability to distinguish between the colors red and green _____________________
Only one X and no y chromosome ____________________
resulting in infertility
Huntington’s disease (HD)
Duchenne Muscular dystrophy
Colorblindness
Turner syndrome

25. What disorder is it? achondroplasia Conjoined twins
Twins that are born joined together ____________________
Males with an extra X chromosome ______________________ (XXY) karyotype; some female features; infertility
Lipids build up in brain causing blindness, retardation, & early death _________________________
Disorder in bone growth so torso __________________________
and head are normal size but arms and legs are short
Conjoined twins
Klinefelter syndrome
Tay-Sachs
achondroplasia