🏷️ LIMITED TIME OFFER: GET 20% OFF GRADE+ YEARLY SUBSCRIPTION →
Log in
HomeClass Notes1,200,000US530,000

BME 80H Lecture Notes - Lecture 12: Hh Blood Group, Abo Blood Group System, Pleiotropy

63 views4 pages
tealantelope800
11 Jun 2018
School
UCSC
Department
Biomolecular Engineering
Course
BME 80H
Professor
Wendy Rothwell

For unlimited access to Class Notes, a Class+ subscription is required.

12th lecture
This is an example of a pleiotropic gene = having more than
one phenotypic effect. This gene affects 2 phenotypes: coat
color and viability.
3. Subvital or semilethal: lethality is only expressed in
some individuals.
penetrance: The probability that an individual will
show a disease phenotype given that they have the
disease-related genotype.
II. Situations where more than one gene affects the phenotype
A. Epistasis: One gene masks the phenotypic effects of
another.
Example: ABO Blood group and the H locus (review figure
3.19/3.17, drawing on first page of this lecture)
-H locus encodes the component (stick) that the A and B sugars
attach to
genotype Blood Type
HH, IA IB AB
Hh, IA IB AB
hh, IA IB O (Bombay phenotype)
The homozygous recessive genotype at the H locus (hh) is
epistatic to (masks) the IA and IB alleles at the ABO locus.
hh, ININ = Bombay Phenotype (where N = any allele)
B. Genetic Heterogeneity: When mutations in different genes
produce the same phenotype
find more resources at oneclass.com
find more resources at oneclass.com
Unlock document

This preview shows page 1 of the document.
Unlock all 4 pages and 3 million more documents.

Already have an account? Log in

Document Summary

This is an example of a pleiotropic gene = having more than one phenotypic effect. This gene affects 2 phenotypes: coat color and viability: subvital or semilethal: lethality is only expressed in some individuals. penetrance: the probability that an individual will show a disease phenotype given that they have the disease-related genotype. Situations where more than one gene affects the phenotype: epistasis: one gene masks the phenotypic effects of another. Example: abo blood group and the h locus (review figure. 3. 19/3. 17, drawing on first page of this lecture) H locus encodes the component (stick) that the a and b sugars attach to genotype. All 3 enzymes when mutated result in no d produced: example: inheritance of deafness in humans. 132 different forms of deafness each resulting from a different mutation. If both parents have a mutation in the same gene: All deaf progeny: aa x aa = all aa (deaf)

Get access

Grade+20% off
$8 USD/m$10 USD/m
Billed $96 USD annually
Grade+
Homework Help
Study Guides
Textbook Solutions
Class Notes
Textbook Notes
Booster Class
40 Verified Answers
Class+
$8 USD/m
Billed $96 USD annually
Class+
Homework Help
Study Guides
Textbook Solutions
Class Notes
Textbook Notes
Booster Class
30 Verified Answers

Related Documents

BME 80H Lecture Notes - Lecture 5: Dihybrid Cross, Mitochondrion, Chromosome
bronzetermite837
BME 80H Lecture Notes - Lecture 11: Abo Blood Group System, Glycosyltransferase, Antigen
tealantelope800
HMB265H1 Chapter Notes - Chapter 6: Hh Blood Group, Epistasis, Summer Squash
cerisetoad631

Related Questions

Match the following definitions with the correct term. (We have not yet cover all of them in class, but you can find them in your reading.)


-

A.

B.

C.

D.

E.

F.

G.

H.

I.

J.

K.

L.

A single mutation affects several traits.


-

A.

B.

C.

D.

E.

F.

G.

H.

I.

J.

K.

L.

The frequency with which individuals of a given genotype manifest the mutant phenotype.


-

A.

B.

C.

D.

E.

F.

G.

H.

I.

J.

K.

L.

A phenotypic trait whose expression depends on the additive effect of a number of genes.


-

A.

B.

C.

D.

E.

F.

G.

H.

I.

J.

K.

L.

Expression of a gene is dependent on whether it has been inherited from the male or female parent.


-

A.

B.

C.

D.

E.

F.

G.

H.

I.

J.

K.

L.

Phenotypic effects on the offspring produced by the maternal genome.


-

A.

B.

C.

D.

E.

F.

G.

H.

I.

J.

K.

L.

Genetic information transmitted by chloroplasts or mitochondria.


-

A.

B.

C.

D.

E.

F.

G.

H.

I.

J.

K.

L.

The degree in which a phenotype for a given trait is expressed.


-

A.

B.

C.

D.

E.

F.

G.

H.

I.

J.

K.

L.

Determines whether two mutations are at the same locus or different loci.


-

A.

B.

C.

D.

E.

F.

G.

H.

I.

J.

K.

L.

Genetic differences that are due to alterations of the DNA that do not included changes in base sequence.


-

A.

B.

C.

D.

E.

F.

G.

H.

I.

J.

K.

L.

Characteristic determined by a gene on a sex chromosome.


-

A.

B.

C.

D.

E.

F.

G.

H.

I.

J.

K.

L.

Characteristic encoded on an autosome that is more readily expressed in one sex.


-

A.

B.

C.

D.

E.

F.

G.

H.

I.

J.

K.

L.

A gene at one locus that masks or suppresses the effect of a gene at a different locus.

A.

pleiotropy

B.

cytoplasmic inheritance

C.

epigenetics

D.

polygeneic inheritance

E.

imprinting

F.

sex-influenced trait

G.

sex-linked trait

H.

penetrance

I.

expressivity

J.

maternal effect

K.

complementation test

L.

epistasis

Expression vectors inprokaryotes do not make functional eukaryotic gene products inbacteria very well because

Answer Not sure which one ?!

· the codon sequence for prokaryotes is differentthan the codon sequence in eukaryotes

· there are no disulfide bridges formed in proteinsnormally made in prokaryotes

· prokaryotic expression vectors cannot translateeukarytic sequences

· eukaryotic genes have introns, and prokaryotesdon't

· eukaryotic genes have exons and prokaryotesdon't


I create a knockout mouseusing the agouti/black fur system \. When I cross the agoutioffspring of the originally engineered mouse, I find a ratio of 2agouti mice to 1 black furred mouse. What is the bestexplanation?

Answer not sure which one?!

· The gene knocked out was recessive.

· The gene knocked out was dominant.

· The gene knocked out was a lethalgene.

· The knockput was integrated into a random spot,and did not knockput the original gene.

A restriction enzyme cuts DNAand leaves the following end

xxCTGCA
xxG

Which of the following could be the sequence of the correspondingend of the other end of the cut DNA?

Answer

· xxG
xxCTGCA

· xxC
xxGTGCA

· xxCCGAT
xxG

· xxGGCTA
xxC


An SNP always occurs dueto

Answer

· a one base-pair change.

· a three base-pair change.

· a single restriction site change.

· a single amino acid change.

· None of these.


I PCR out a mutated gene in apatient with Lisenbee chorea (the inability to dance in acoordinated fashion) and I compare it to another patient with thatsame disease phenotype. One subject had a mutation on chromosome 4,and the other subject couldn't rock it because of a mutation onchromosome 5. This is an exampe of

Answer

· pleitropy

· locus heterogeneity

· allelic heterogeneity

· dominant negative mutation

· penetrance

In his experiments, Mendelnoted that when two traits are involved in a genetic cross, theyare inherited independently of each other. Though Mendel didn'tknow about chromosomes, this still holds true (mostly)because

Answer

· genes on the same chromosome are often mixedthrough meiotic crossover during the formation ofgametes.

· variant alleles of the same gene do not interferewith the phenotypic expression of the gentoype in different geneticloci.

· most higher organisms are diploid, making only twoalleles available for every genetic locus, and there is a 50/50chance of geting either allele from a single parent.

· expression of phenotypes can vary from thegenotypes because of encironmantal influences.

· chromosomes often recombine

Anticipation is caused by amutation that increases in expressivity over subsequentgenerations.

Answer

· True

· False

Question 44

I have a genotype that shouldproduce a specific phenotype, but some of the individuals with thegenotype do not demonstrate any evidence of the phenotype. I wouldconsider this an example of

Answer

· allelic heterogeneity.

· locus heterogeneity.

· penetrance.

· expressitivity.

· sheer luck.

Question

Which of the following doesnot occur during the PCR reactions?

Answer

· Changes in the reaction temperature by athermocycler

· Denaturation at high temperatures

· Synthesis of oligonucleotide primers

· Extension of primers by DNA polymerase

· Annealing of oligonucleotide primers

Question

DNA markers, or variantnon-coding regions of DNA, are DNA polymorphisms that are usefulfor genetic mapping.

Answer

· True

· False

A mosaic is an organismwith

Answer

· multiple genotypes within one organism

· multiple alleles within one genotype

· more than one color of fur

· transgenes added to the zygote beforedevelopement

· a wt phenotype but a mutated genotype

Question

Genotype causesphenotype.

Answer

· No, gentoype just influences phenotype.

· Yes, genotype is the DNA sequence that createsphenotype.

Question

A true genetic chimera can becreated by

Answer

· mutating a gene early on in the development of anorganism resulting in different alleles being present in theadult

· multiple fertilized eggs or zygotes fusing to formone embryo

· adding a transgene to the genome of an organismduring fetal development only

· adding cells of a different species to an adultorganism

· adding a transgene to the genome of an animal atany stage in development

Question

The ABO blood group can bestbe explained by the concept of _______.

Answer

· dominant traits

· recessive traits

· allelic heterogeneity

· locus heterogeneity

· vampirism

If a loss of functionmutation creates a dominant phenotype, it may be becauseof

Answer

· haploinsufficiency

· penetrance

· expressivity

· allelic heterogeneity

· locus heterogeneity

Please select the best matchfor each.

Answer

· PCR: Technique used to generatecopies of a DNA fragment

· Southern blot : Screeningprocedure used to assay DNA fragments

· RFLPs : DNA fragments generatedby restriction enzymes that vary in length betweenindividuals

· Northern blot : Screeningprocedure used to assay mRNA fragments

· Electrophoresis Movement ofmacromolecules in an electrical field

Answer

A.

Screening procedure used toassay DNA fragments

B.

Movement ofmacromolecules in an electrical field

C.

Screening procedure used toassay mRNA fragments

D.

DNA fragments generated byrestriction enzymes that vary in length betweenindividuals

E.

Technique used to generatecopies of a DNA fragment

A gene mutates, and theprotein produced has a novel way of interacting with the cell, andcreates a new phenotype because of this new functionality. This iscalled

Answer

· pleitropy

· locus heterogeneity

· allelic heterogeneity

· dominant negative mutation

· gain of function dominant mutation

Question 62

Mutations in the somaticchromosomes may be inherited by the next generation.

Answer

· True

· False


A degenerate PCR primer withmany variant sequences must be used to make multiple copies of agene

Answer

· if only the protein sequence of the gene productis known to construct the primers

· if the DNA you are using is cDNA to constructthe primers

· if the DNA you are using is genomic DNA to becopied

· if the DNA you are trying to copy iscDNA

· if the vector is prokaryotic and the transformedcell is eukarytotic

Question

Please select the best matchfor each term.

Answer

· Restriction enzyme


· PCR C

· Plasmid

· YAC A

· Dideoxynucleotide

Answer

A.

Endonuclease isolated frombacteria

B.

Eukaryotic cloningvector

C.

Method for amplification ofDNA sequences

D.

Small circular fragment ofDNA

E.

Molecule used in DNAsequencing

Question

A couple goes on MauryPovitch, and the results are in: you are not the father. But noother man impregnated the female (granted, unlikely for a MauryPovitch guest, but work with me here) and he must be the father.DNA analysis claims otherwise, though the child definitely wasmom's (poor thing). What may be going on here?

Answer

· the child is parthenogenic because the motheractually impregnated herself like a shark, and the child's DNA isall mom's

· the child had a mutation that changed the genethat is used to trace paternity

· the child is a mosaic because he is actually a setof twins fused early during fetal development, and therefore camefrom 2 eggs and 2 sperm

· the dad may have germ-line mosaicism, meaning thatthe genotype of his sperm is different from his somaticgenotype

· mitochondrial DNA only comes from mom, so there isno way to tell whobthe baby's father is




___1. Nationally, the most common cause of Down Syndrome is
a. nondisjunction of Chromosome 21 during meiosis
b. translocation of Chromosome 21 onto another chromosome
c. inversion of a large section of Chromosome 21
d. deletion of the Down Syndrome gene
___2. In humans, sex is determined by
a. The presence or absence of the Y chromosome
b. The ratio of X chromosomes to sets of autosomes
c. The temperature during fetal development
d. Which parent is stronger at the time of conception
___3. A translocation is
a. a chromosomal abnormality in which a piece of one chromosome breaks off and attaches to a different chromosome
b. an abnormality in which the chromosomes are translocated out of the nucleus
c. a condition in which the chromosome has broken in two places and come back together with the middle segment backward
d. an abnormality in which there is an extra copy of one chromosome
___ 4. In snapdragons, a red-flowered plant crossed with a white-flowered plant produces all pink-flowered offspring. But crossing two pink-flowered plants produces red, pink, and white in a 1:2:1 ratio. This is a good example of
a. Incomplete dominance
b. Dominance of the red allele over the white allele
c. Lethal effects of the pink allele
d. Sex-linkage of the flower-color alleles
___ 5. If a person with type AB blood marries a person with Type O blood, what blood types are possible in their children? (Assume this trait is a single-gene trait, not complicated by interaction with other genes).
a. A, B, AB, or O
b. A or B only
c. AB or O only
d. AB only 2
___6. In what phase of meiosis are haploid nuclei first formed? a. Anaphase I b. Metaphase II c. Telophase II d. Metaphase I e. Telophase I
___7. What is the phenotype of a heterozygous tall pea plant? a. tall b. Tt c. TT d. tt e. dominant
___ 8. If genes A and B are far apart on a chromosome, and A and C are close together, which of the following observations is expected?
a. Crossing over will occur more often between A and C than between A and B
b. Crossing over will occur at equal frequencies between A and C, and between A and B
c. Crossing over will occur more often between A and B than between A and C
___9. Sometimes an organism’s genotype for one gene masks the effect of a different gene. This phenomenon is called
a. Dominance
b. Incomplete dominance
c. Co-dominance
d. Epistasis
e. Variable expressivity
___10. The dominant allele of a gene is
a. The one that is expressed most often in a population
b. The one that is expressed most often in any particular cross
c. The one that is expressed in an individual that has two different alleles
d. The one that is most healthy to have, that gives the greatest fitness
___11. In human cells, DNA replication occurs
a. In S phase of interphase
b. In G1 phase of interphase
c. In G2 phase of interphase
d. In prophase of mitosis
e. Whenever the cell needs to read the DNA to make proteins
___ 12. A process in which recipient cells take up genes from DNA molecules floating free in the surrounding medium is called
a. conjugation
b. specialized transduction
c. generalized transduction
d. transformation 3
___ 13. Most calico cats are female. However, a few rare males are observed. What is the genotype of a male calico cat?
a. X BX 0
b. X OY
c. X BY
d. X BYY
e. X BX OY
___ 14. A type of red-green color-blindness is a sex-linked (X-linked) recessive trait in humans. Can a woman have this type of color-blindness?
a. Yes, a woman could be color-blind if her mother and father were both heterozygous.
b. Yes, a woman could be color-blind but only if she has an abnormal number of sex chromosomes.
c. No, women can't show sex-linked traits because they lack a Y chromosome.
d. No, women can't show sex-linked traits because they have two X chromosomes.
e. Yes, a woman could be color-blind if her father was color-blind and her mother was a carrier (heterozygous).