Chapter 3

A. Gene function

Genes and protein synthesis and mutation(diagram)

B. Genetic diseases

Identification of genes

Pedigrees/DNA markers

Diseases (PKU, Albinism, CF,

Huntington Disease, DMD)

C. Use/Misuse of genetic information

Genetic tests

Prenatal testing

PCR (polymnerase chain reaction)Eugenics (positive/negative)

How proteins are made (protein synthesis):

tRNA

RNA Polymerase ribosomes (protein, rRNA)

DNA mRNA protein4 "letters” 4 "letters” 20 "letters"

transcription translation(in nucleus) (in cytoplasm)

What is a “gene?”

the DNA from a part of a chromosome that “codes” for a particular product (protein)

Chromosomes have from50 -250 Mb (Megabytes) of nucleotides50,000,000 to 250,000,000

nucleotides

a chromosome

double helix

Review DNA Replication

• DNA is double stranded• Base pairing between strands

A = TC G

Thymine

Adenine

Cytosine

Guanine

Review DNA Replication

• DNA is unwound

• DNA Polymerase finds compliment to each nucleotide and makes new strands

• Two identical molecules of DNA

Review DNA info

nucleic aciddouble-strandedfour nucleotides

A, C, G, Tbase-pairing

RNA info

nucleic acidsingle-strandedfour nucleotides

A, C, G, Ubase-pairing

Protein synthesis (A)•Unwind DNA

•Make strand of RNA complimentary to one DNA strand

•RNA Polymerase is the enzyme

Protein synthesis

Fig 25.8

Protein synthesis (A)

Fig 25.8

•RNA produced is call mRNA (messenger)•It is produced in the nucleus•The information has been re-written

from one nucleic acid “dialect” (DNA) toanother (RNA)

•Process is called transcription

C. How proteins are made (protein synthesis):

tRNA

RNA Polymerase ribosomes (protein, rRNA)

DNA mRNA protein4 "letters” 4 "letters” 20 "letters"

transcription translation

(in nucleus) (in cytoplasm)

Protein synthesis (B)

Fig 25.8

•mRNA is moved to the cytoplasm•It will bind to the ribosome

proteins rRNA (ribosomal RNA)

Remember where the ribosomes are ?

Protein synthesis (B)

Fig 25.8

•tRNAcarriesamino acid

hasanticodon

Protein synthesis (B)

Fig 25.8

•tRNAcarriesamino acid

hasanticodon

Fig 25.10

Protein synthesis (B)

Fig 25.8

•tRNA

The tRNA with a particular anticodon (GCU) will always carry the same amino acid.

(Complimentary codon is. . .

Protein synthesis (B)

Fig 25.8

•tRNA

The tRNA with a particular anticodon (GCU) will always carry the same amino acid.

(Complimentary codon is CGA

Protein synthesis (B)

Fig 25.8

Fig 25.6

mRNAsequence

Protein synthesis (B)

Fig 25.8

•mRNA is moved to the cytoplasm•It will bind to the ribosome

proteins rRNA (ribosomal RNA)

Fig 25.12

Protein synthesis (B)

Fig 25.8

Fig 25.6

mRNAsequence

Protein synthesis (B)

Fig 25.8

•mRNA is moved to the cytoplasm•It will bind to the ribosome

proteins rRNA (ribosomal RNA)

Fig 25.12

Fig 25.8Fig 25.12

Fig 25.8Fig 25.12

fig. 3-1

fig. 3-3

fig. 3-4

fig. 3-5

Review Outline 2C. How proteins are made (protein synthesis):

tRNA

RNA Polymerase ribosomes (protein, rRNA)

DNA mRNA protein4 "letters” 4 "letters” 20 "letters"

transcription translation

(in nucleus) (in cytoplasm)

Fig 25.8

Fig 25.6

If you know the DNA sequence, you can determine the mRNA sequence and can determine what order the amino acids will be arranged in the protein…

Fig 25.8

Fig 25.6

If you know the DNA sequence, you can determine the mRNA sequence and can determine what order the amino acids will be arranged in the protein…

…so lets make some hemoglobin.

Fig 25.8

Fig 25.6

Everybody gets an job or identity

Enzymes (2) (make polymers)

DNA nucleotide (A=T; C=G)

RNA nucleotide (A=U;C=G)

tRNA (find and carry your amino acid)

Amino acid (sit there and look pretty)

Fig 25.8

Fig 25.6

Everybody gets an job or identity

Enzymes (2) (make polymers)

DNA nucleotide (A=T; C=G)

RNA nucleotide (A=U;C=G)

tRNA (find and carry your amino acid)

Thymine

Adenine

Cytosine

Guanine

Chapter 3

A. Gene function

Genes and protein synthesis and mutation

B. Genetic diseases

Identification of genes

Pedigrees/DNA markers

Diseases (PKU, Albinism, CF,

Huntington Disease, DMD)

C. Use/Misuse of genetic information

Genetic tests

Prenatal testing

PCR (polymnerase chain reaction)Eugenics (positive/negative)

Identification of genes

pedigrees

Identification of genes

pedigrees

fig 3-7

DNA markersUnique place on a chromosome that can be detected with a probe.

DNA markersUnique place on a chromosome that can be detected with a probe.

Follow different DNA markers that fit the pedigree

Pedigree =

=

Pedigree = disease

= normal

Analysis ?

Define terms

Define terms:

N = normal

n = diseased (e.g., CF)

nn nn

nn nn

N_

N_ N_

N_ N_N_N_

nn nn

N?

N_ N_

N_ N_N_N?

nn nn

Nn

N_ N_

N_ N_N_Nn

nn nn

Nn

N? N?

N_ N_N_Nn

nn nn

Nn

N? N?

N_ N_N_Nn

8 yrs

Kirstin

10 yrs

Courtney

Chapter 3

A. Gene function

Genes and protein synthesis and mutation

B. Genetic diseases

Identification of genes

Pedigrees/DNA markers

Diseases (PKU, Albinism, CF,

Huntington Disease, DMD)

C. Use/Misuse of genetic information

Genetic tests

Prenatal testing

PCR (polymnerase chain reaction)Eugenics (positive/negative)

B. Genetic diseases

Diseases (PKU, Albinism, CF,

Huntington Disease, DMD)

autosomal recessive human diseases

autosomal - on chromosomes 1-22 (not on X or Y)

recessive - not dominant

B. Genetic diseases

Diseases (PKU, Albinism, CF,

Huntington Disease, DMD)

autosomal recessive human diseases

autosomal - on chromosomes 1-22 (not on X or Y)

recessive - not dominant

B. Genetic diseases

Diseases (PKU, Albinism, CF,

Huntington Disease, DMD)

autosomal recessive human diseases

autosomal - on chromosomes 1-22 (not on X or Y)

recessive - not dominant

B. Genetic diseases

Diseases (PKU, Albinism, CF,

Huntington Disease, DMD)

autosomal recessive human diseases

CF cystic fibrosis chromosome 7

defective chloride transport protein

PKU

defective enzyme to breakdown phenyalanine

B. Genetic diseases

Diseases (PKU, Albinism, CF,

Huntington Disease, DMD)

autosomal recessive human diseases

CF cystic fibrosis chromosome 7

defective chloride transport protein

PKU defective enzyme to breakdown phenyalanine

B. Genetic diseases

Diseases (PKU, Albinism, CF,

Huntington Disease, DMD)

autosomal recessive human diseases

CF cystic fibrosis chromosome 7

defective chloride transport protein

PKU defective enzyme to breakdown phenyalanine

Albinism defective enzyme for making pigment

fig 3-10

B. Genetic diseases

Diseases (PKU, Albinism, CF,

Huntington Disease, DMD)

autosomal recessive human diseases

CF cystic fibrosis chromosome 7

defective chloride transport protein

PKU defective enzyme to breakdown phenyalanine

Albinism defective enzyme for making pigment

Tay Sachs missing Hex A enzyme, ganglioside accumulates

Autosomal Dominant Diseases

• Huntington Disease• Myotonic Dystrophy

Autosomal Dominant Diseases

Chapter 3

A. Gene function

Genes and protein synthesis and mutation

B. Genetic diseases

Identification of genes

Pedigrees/DNA markers

Diseases (PKU, Albinism, CF,

Huntington Disease, DMD)

C. Use/Misuse of genetic information

Genetic tests

Prenatal testing

PCR (polymnerase chain reaction)Eugenics (positive/negative)

X-linked recessive

Chapter 3

A. Gene function

Genes and protein synthesis and mutation

B. Genetic diseases

Identification of genes

Pedigrees/DNA markers

Diseases (PKU, Albinism, CF,

Huntington Disease, DMD)

C. Use/Misuse of genetic information

Genetic tests

Prenatal testing

PCR (polymnerase chain reaction)Eugenics (positive/negative)

Chapter 3

C. Use/Misuse of genetic information

Genetic tests

Prenatal testing

PCR (polymerase chain reaction)Eugenics (positive/negative)

Chapter 3

C. Use/Misuse of genetic information

Genetic tests ?

Chapter 3

C. Use/Misuse of genetic information

Genetic tests

It is possible to test for many different genetic

diseases.

Is it “right” to do so?

Who pays (it’s expensive)?

Chapter 3

C. Use/Misuse of genetic information

Genetic tests

Prenatal testing

Amniocentesis

Chorionic villi sampling

PCR (polymerase chain reaction)Eugenics (positive/negative)

Fig 3-11

fig 3-11

Chapter 3

C. Use/Misuse of genetic information

Genetic tests

Prenatal testing

If you found out an unborn child had a genetic

disease what would you do?

PCR (polymerase chain reaction)Eugenics (positive/negative)

Chapter 3

C. Use/Misuse of genetic information

Genetic tests

Prenatal testing

PCR (polymerase chain reaction)

a technique used to examine very small samples

fig 3-12

Chapter 3

A. Gene function

Genes and protein synthesis and mutation

B. Genetic diseases

Identification of genes

Pedigrees/DNA markers

Diseases (PKU, Albinism, CF,

Huntington Disease, DMD)

C. Use/Misuse of genetic information

Genetic tests

Prenatal testing

PCR (polymnerase chain reaction)Eugenics (positive/negative)

Eugenics“good birth”

Individuals have genetic identity genotype

Populations have genetic identity gene pool

Eugenics is working to change the gene pool

Positive use the “best” to breed (cattle, plants)

Negative prevent “inferior” genes from passing on

Eugenics“good birth”

Individuals have genetic identity genotype

Populations have genetic identity gene pool

Eugenics is working to change the gene pool

Positive use the “best” to breed (cattle, plants)

Negative prevent “inferior” genes from passing on

Eugenics“good birth”

Individuals have genetic identity genotype

Populations have genetic identity gene pool

Eugenics is working to change the gene pool

Is it right?