Yellow dots mark the locus of a specific gene on a homologous

1
Yellow dots mark the locus of a specific gene on
a homologous pair of human chromosomes
2
(No Transcript)
3
The chromosomal basis for Mendels Laws
4
(No Transcript)
5
(No Transcript)
6
(No Transcript)
7
Sex-linked inheritance
8
Evidence for linked genes in Drosophila
9
Page 9 3
P EETTBB X eettbb
etb
ETB EeTtBb
F1 cross EeTtBb X EeTtBb
F1p 100 Long ears, brown tails, and brown eyes
ETB ETb etB etb
ETB EETTBB EETTBb EeTtBB EeTtBb
ETb EETTBb EETTbb EeTtBb EeTtbb
etB EeTtBB EeTtBb eettBB eettBb
etb EeTtBb EeTtbb eettBb eettbb
F2p 56.25 Long, brown, brown 18.75 Long,
brown, blue 18.75 short, cotton, brown 6.25
short, cotton, blue
10
Page 9 4
P EEttbb X eeTT BB
eTB
Etb EeTtBb
F1 cross EeTtBb X EeTtBb
F1p 100 Long ears, brown tails, and brown eyes
EtB Etb eTB eTb
EtB EEttBB EEttBb EeTtBB EeTtBb
Etb EEttBb EEttbb EeTtBb EeTtbb
eTB EeTtBB EeTtBb eeTTBB eeTTBb
eTb EeTtBb EeTtbb eeTTBb eeTTbb
F2p 18.75 Long, cotton, brown 37.5 Long,
brown, brown 6.25 Long, cotton, blue 12.5 Long,
brown, blue 18.75 short, brown, brown 6.25
short brown, blue
11
Production of recombinant gametes by a dihybrid
female
12
(No Transcript)
13
page 10 1
636 Gray body, normal wings 50 Gray body,
vestigial wings 253 Black body, vestigial
wings 61 black body, normal wings
Phenotypes s If linked Actual s s If Not linked
Gray, normal
Gray, vestigial
Black, normal
Black, vestigial
75 25
63.6 5.0 6.1 25.3
56.25 18.75 18.75 6.25
Yes, 11.1 map units
14
page 10 2
364 Long ears, brown fur 6 Long ears, white
fur 122 short ears, white fur 8 short ears, brown
fur
Phenotypes s If linked Actual s s If Not linked
Long, brown
Long, white
Short, brown
Short, white
72.8 1.2 1.6 24.4
56.25 18.75 18.75 6.25
75 25
Yes, 2.8 map units
15
Page 11 4
P BBNN X bbnn
F1 cross BbNn X BbNn
bn
BN BbNn
BN bn
BN BBNN BbNn
bn BbNn bbnn
F1p 100 brown eyes, normal wings
F2p
75-6
69 Brown eyes, normal wings
4 Brown eyes, vestigial wings 4 Red eyes,
normal wings
25-2
23 Red eyes, vestigial wings
.75 .25 x.08 x.08 0.06 0.02
16
Page 11 5
P llgg X LLGG
F1 cross LlGg X LlGg
LG
lg LlGg
LG lg
LG LLGG LlGg
lg LlGg llgg
F1p 100 Long proboscis, clear wings
F2p
61.5 Long proboscis, clear wings
75-13.5
9 Long proboscis, gray wings 9 Short
proboscis, clear wings
25-4.5
20.5 Short proboscis, gray wings
.75 .25 x.18 x.18 0.135 0.045
17
Recombination frequencies can be used to
construct a genetic map.
18
A partial genetic map of a Drosophila chromosome
19
(No Transcript)
20
(No Transcript)
21
(No Transcript)
22
(No Transcript)
23
Chromosomal systems of sex determination. In
human males the SRY gene codes a protein that
regulates genes that triggers the development of
testes and many other maleness genes.
24
(No Transcript)
25
(No Transcript)
26
The transmission of sex-linked recessive
traits Sex-linked traits in humans include
red-green color blindness hemophilia, and
Duchenne muscular dystrophy
27
(No Transcript)
28
X inactivation and the tortoiseshell cat. The
tortoiseshell gene is on the X chromosome and
the phenotype requires the present of both
alleles (one on each X chromosome) The XIST gene
on one X chromosome is active and codes RNA which
coats that X chromosome which initiates the
methylation of that X and causes it to condense
and form a Barr body
29
Meiotic nondisjunction
30
Nondisjunction results in aneuploidy XO-Turner
Syndrome only human monosomy that survives
no Barr bodies/cell XXY-Klinefelter Syndrome one
Barr body/cell XYY Super male greater chance of
violence XXX XXXX Super female greater chance
of violence 2 or 3 Barr bodies/cell Trisomy
21-Down syndrome-can also be caused by
translocation of part of chromosome
21 cri du chat-deletion of part of chromosome
5 CML-translocation of part of 22 to the tip of 9
31
(No Transcript)
32
(No Transcript)
33
(No Transcript)
34
(No Transcript)
35
A tetraploid mammal??
36
(No Transcript)
37
(No Transcript)
38
(No Transcript)
39
Prader-Willi syndrome when inherited from
male Angelman syndrome when inherited from
female Genomic Imprinting is accomplished by
methylation of genes to turn them off silence
them or areas near them to turn them on. Male
imprinting is designed to produce a larger,
stronger, fetus and female imprinting is designed
to produce a smaller fetus.
40
Genomic imprinting is an attempt by the male to
produce larger, stronger offspring the female
imprints are an attempt to produce smaller less
energy draining offspring fragile X
syndrome-one section of the X hangs by a thin
thread of noncoiled DNA which is composed of long
sets of triplet repeats CGG genomic imprinting
by the mother is more likely to cause the syndrome
41
Variegated leaves caused by extranuclear genes
that are inherited from the ovum.
Where did all your mitochondria come from?
42
(No Transcript)