Download Genome - chromosomes - genes

Draw the pedigree of a color blind father
and an unaffected mother!
CC
C
Cc
c
C
Cc
2
Chromosomes
Basic terminology:
Genome - chromosomes - genes - DNA
histon
DNA
30 nm
bacteria
Haploid chromosome set:
3
1
frog
26
cat
human
38
46
4
kromoszOma
more DNA History
DNA History
1955: 46 human chromosomes
1961: mRNA
1975: DNA-sequencing
1982: gene bank databases
1983: PCR (polymerase chain reaction)
J. D. Watson
J. D. Watson
F. H. C. Crick
1953
DNA stucture
1953
5
F. H. C. Crick
2008
Watson’s genom
2003
Finished Human Genom Project 6
1
DNA – the genetic information
„Size does matter”
☺
2 nm
P
A
O
T
O
P
P
O
C
G
O
3,4 nm
10 bp
P
P
G
O
C
O
P
P
O
T
A
O
P
base
pairs
„the total length” = 1 m
7
What is the inherited information: „the code”
15601
15661
15721
15781
15841
15901
15961
16021
16081
16141
16201
16261
16321
16381
ACTCGCTCGT
TCATCGTGAG
TCTACTCCGA
CGTCCCTGTC
GCTGGGGCGG
CTCGCGACCT
CCGTCTGTCT
AACAGGCGAC
AGCTGGACAG
ACACACTGCC
GAAGGAGGCT
GTGTGTGGGG
GATGGAGCCC
CCTCTGCGGC
GTGCGTGAGC
CCTGGCGGCC
GGTGAGCCGC
CCTACGGAGG
CGGCAGGGGC
TCCACCCGCT
TGGCGTCTGT
TTTGTCAAGC
ACAGGCAGAT
ACAGCCACTG
CACAGCTCGC
ACCAGGCCCC
ACACTCCACA
CAGAGAAAAG
GTGGCCACCG
GCCGACCTCC
GTCCGGCCGC
ACCCGGCGCG
GCTGCGCCTT
GCGCTGTCTG
TATCCAGGAG
CCAGTCCCCT
GCAGGCTCAG
CCCACCACAC
AGGGGAGACC
TGCTGAGAAC
CCAGGTCTGG
CAGCTTAGGG
AGCGCGCCCT
TCCTCGCTCT
ACGAGCATCC
ACCCGGCCCC
GTCCCTCGGC
TCCCCCGACC
ATGCCCGTCC
CCGTAGCTGG
CCCCCTGGCT
ACACCTAGTG
TGGGCTGGAC
CCTGGGGGGA
CCCTCGAGTG
CTGAGCTGGA
GCAGACGCCC
CCTGGTGCTG
TCACCTGCTC
TTTCTGGTGC
GATACACCCA
CTCGTTCCTC
TTCTATCCAG
ATTTCACCTC
GCCGTGGGAC
CAGATGCTGG
AAAACCCAGG
AGCCTGAGGG
GGTCGGCCTT
GACGCGGTGT
ACCAACTCCT
CCGCTCTTCG
CTCGGTTCCC
GGAGCTTCCA
CCGCCGCCAC
TTCTCCTTCC
GGACCCCGGA
CAGGGCAGCC
ACACACACAC
CACACCCCCA
GGAGGGGAGG
GGAATTGGGG
GGTGCCAGCC
CCCCGACTGT
8
Basic functions of the DNA:
replication and directing protein synthesis
the nucleotide sequence
The genomic information
„Post-genomic era”
9
DNA replication during the process of cell division
10
The „Central Dogma” of Molecular Biology
DNA
Gene expression
1. double helix unzips,
separating the paired
bases
2. each strand serves as
template for the
production of the
complementary strand
3. Two identical copies of
the original DNA
11
mRNA (exons)
protein
12
2
The genetic code
3 letters (base-pairs) = 1 codon =
1 amino acid
The genetic code
TGCGTGAGCGTGGCCACCGAG
Cys Val Ser Val Ala Thr Glu
The code for protein synthesis (exons) is hidden among other
letters (introns).
Second letter
C
A
G
Third letter
First letter
U
U
C
A
G
TGCGTGAGCGTGGCCACCGAG
Phe
Tyr
Cys U
C
Ser
Cys
Val Ser Val Stop
Ala ThrStop
Glu A
Leu
Stop
Trp G
U
His
Leu
Pro
Arg C
A
Gln
G
Asn
Ser U
Ile
C
Thr
Lys
Arg A
Met Start
G
U
Asp
Val
Ala
Gly C
A
Glu
G
The information is:
- not overlapping,
- does not have coma
- universal
- determined
- but redundant
MDIOEQLAYAGTHEIWHFIEO
WLDHRZUQOALKOCOSTWLOU
QNDOGQURUEUAHFKEEPSMN
DPRWTHEELIAMNHOUSEQRT
AHQILKAKHERDIXYYTRAEQ
JASAFEUNZATOKOGETHERU
13
14
alternative splicing
The genetic code
MDIOEQLAYAGTHEIWHFIEO
WLDHRZUQOALKOCOSTWLOU
QNDOGQURUEUAHFKEEPSMN
DPRWTHEELIAMNHOUSEQRT
AHQILKAKHERDIXYYTRAEQ
JASAFEUNZATOKOGETHERU
Exons carry the information necessary for protein synthesis.
Introns are spliced out before the RNA leaves the nuclus.
Only exonal regions exit the nucleus
to be translated into amino acid sequences.
Genes have an exon-intron structure:
MDIOEQLAYAGTHEIWHFIEO
WLDHRZUQOALKOCOSTWLOU
QNDOGQURUEUAHFKEEPSMN
DPRWTHEELIAMNHOUSEQRT
AHQILKAKHERDIXYYTRAEQ
JASAFEUNZATOKOGETHERU
15
16
Regulation of gene expression
Genetic polymorphisms :
Promoter (regulatory) region
–521CT
SNP
Transcribable - Coding region
(e.g. exons I, II and III)
I.
II.
III. DNA
G CA C TAC C
C GTGATGG
G CATTAC C
C G TAAT G G
Transcription
factors
Single Nucleotide
Polymorphism
Quantity
Quality
17
VNTR
2 repeat
3 repeat
4 repeat
5 repeat
Variable Number
of Tandem Repeats
18
3
Determining polimorphisms
3. PCR (polimerase chain reaction)
1. DNA sampling
PCR
blod
buccal swabs
Whole Human genome
2 x 3x109 bp
2 x 23 chomosomes
2. DNA isolation
(2 x ) 102-103 bp PCR product
From a DNA fragment
19
20
Selected readings
Textbook: Ch 4 page 41-49.
• DNA – the basis of heredity (chromosomes,
nucleotide, basepair, genome, genes, alleles)
• Basic functions of the DNA: reproduction and
coding proteines
The outline from this lecture presentation
will be available at the course website!
• The "Central Dogma" of Molecular Biology, DNA,
mRNA, exon, intron, splicing)
• Gene expression (promoter and coding region)
• Polimorphic regions (SNP and VNTR)
and their determination by PCR method
21
22
• The genetic code might change in any of the
followings. Which change would most probably
cause a mutation which would cause a disease?
• Intron
• Exon
• Promoter
• mRNA
• Genome
23
4