1. a+ --> a- mutation (forward mutation)
a > a+ reverse mutation (reversion)

2. Presence of pink pigment + / -
Four-o’clock plants
Incomplete dominance the term used to describe the general case in which the phenotype of a heterozygote is intermediate between those of the two homozygotes, on some quantitative scale of measurement

3. Point mutations at the molecular level
Purine replaced by a different purine; pyrimidine replaced by a different pyrimidine: TRANSITIONS
Purine replaced by a pyrimidine; pyrimidine replaced by a purin:
TRANSVERSIONS

6. Animation ed.9: 9.2&9.17
TRANSLATION 6

8. Animation ed.9: 9.2&9.17
TRANSLATION 8

13. Now, insertions and deletions of base pairs:

15. Selection of auxotrophs by filter enrichment
Forward mutation-A mutation that converts
a wild-type allele into a mutant allele

16. Reverse mutation-The production of a wild-type gene from a mutant gene

18. Intragenic suppressor
Equivalent reversion
UCC (Ser) forward UGC (Cys) reverse AGC (Ser)
Wild type Mutant Wild type
CGC (Arg, basic) forward CCC (Proline) reverse CAC (His, basic)
Wild type Mutant Pseudo-wild type

19. Intragenic suppressor

20. Intergenic suppressor

21. Intergenic suppressor
Nonsense
suppressor

23. Chromosome transmission fidelity (Ctf) assay
non-essential Chromosome Fragment M
SUP11
ade2-101 WT
ade2-101
kar3D
sic1D
rad50D
xrs2D
CIN mutant
ade1-101
ade2-101

24. Animation ed9: 9.19a
Nonsense mutation

25. Animation ed9: 9.19b
Nonsense suppressor

26. rodns and suppressor-tRNA together give WT phenotype
Animation 9.19c
Nonsense suppression
rodns and suppressor-tRNA together give WT phenotype

27. Regulatory
Coding

30. Using genomic sequence to find a specific gene

31. When doing GENETIC mapping, Molecular Markers can be used as a locus
Single Nucleotide Polymorphisms (SNPs)
AACGTCATCG vs. AACGTTATCG
Microsatellites (variable # of short repeats)
CGCGCG vs. CGCGCGCGCG vs. CGCG
Restriction Fragment Length Polymorphism (RFLP)
SNP leading to a loss/gain of a restriction cut site

32. When doing GENETIC mapping, Molecular Markers can be used as a locus
Almost all SNPs, Microsatellites, etc. are SILENT,
and there are millions of them
They are mile-markers,
not destinations!
אבני דרך,
ולא יעדים!

33. A specific gene, the breast cancer gene BRCA1 was found
By using the genomic map at increasing levels of resolution

34. X Is there linkage between a mutant gene/phenotype and a SNP?
USE standard genetic mapping technique,
with SNP alternative sequences as “phenotype”
B= bad hair, Dominant
SNP ACGTC..
SNP1’ ACGCC..
SNP GCTAA..
SNP2’ GCAAA..
SNP GTAAC..
SNP3’ GTCAC..
B 2’ / b 2 X
1/1’ /1
B/b b/b
2/2’ /2
3/3’ /3
B/b
b/b
1/1’ 25%
1/ %
2/2’ 47%
2/ %
2/2’ 3%
2/ %
3/3’ 25%
3/ %
SO…B is 6 cM from SNP2, and is unlinked to SNP 1 or 3 34

35. X Is there linkage between a mutant gene/phenotype and a SNP?
USE standard genetic mapping technique,
with SNP alternative sequences as “phenotype”
B= bad hair, Dominant
SNP ACGTC..
SNP1’ ACGCC..
SNP GCTAA..
SNP2’ GCAAA..
SNP GTAAC..
SNP3’ GTCAC.. X
1/1’ /1
B/b b/b
2/2’ /2
3/3’ /3
We have the ENTIRE genome sequence of mouse,
so we know where the SNPs are
Now-do this while checking the sequence of THOUSANDS of SNPs
SO…B is 6 cM from SNP2, and is unlinked to SNP 1 or 3 35

36. The logic of creating sequence map of the genome

37. genomic DNA from genomic clone libraries
Physical maps are maps of the order, overlap, and orientation of physically
isolated pieces of the genome-in other words, maps of the distribution of the cloned
genomic DNA from genomic clone libraries

38. Part of the automated production line of a major human genome sequencing center

39. A specific gene can be found in the genomic sequence by
matching linkage and cytological maps with the
Genome sequence

44. CGCGCG
vs. CGCGCGCGCG
vs. CGCG

48. Complementation groups
Mutagenesis
Plate to select for
phenotype of interest

49. are mutated in the same gene Same complementation group
Complementation groups
First, we need to catalogue our mutants to complementation groups (Total of 138 mutants were isolated in the original CTF screen).
Mutant#1
Mutant#2
Diploid x x x
GENE1 x
GENE1
GENE1
Mate
GENE1
Diploid still shows
CTF phenotype
Mutant#1 and Mutant#2
are mutated in the same gene
Same complementation group

50. are mutated in different genes Different complementation groups
Mutant#3
Mutant#4
Diploid
GENE10
GENE9 x x x
GENE10
GENE9
Mate
GENE9
GENE10
Diploid dont show
CTF phenotype
Mutant#3 and Mutant#4
are mutated in different genes
Different complementation groups

51. Chromosome Transmission Fidelity (ctf) Mutants
Complementation groups
Chromosome Transmission Fidelity (ctf) Mutants
Total # of mutant isolates: 138
19 Complementation Groups Undesignated (single member) 37
Estimated total # of genes represented ~ 50 ctf genes

53. A situation in which the third nucleotide
WOBBLE
A situation in which the third nucleotide
of an anticodon (at the 5’ end) can form two alignments.
This third nucleotide can form hydrogen bonds not only with its
Normal complementary nucleotide in the third position but
Also with different nucleotide in the position.

55. I stands for inosine, one of the rare bases found in tRNA, often in anticodon

57. The genetic code is said to be degenerate because in many cases
MESSAGE
The genetic code is said to be degenerate because in many cases
more then one codon is assigned to a single amino acid, and, in addition,
several codons can pair with more then on anticodon (wobble)