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An Introduction to Pre-implantation Genetic Diagnosis (PGD)
An Introduction to Pre-implantation Genetic Diagnosis (PGD)

... - Cystic fibrosis (autosomal recessive; ~85% for common allele mutation) - Huntington’s disease (autosomal dominant) - Thalassemias (autosomal recessive blood disorder) - Duchenne muscular dystrophy (X-linked recessive) ...
Final Exam Genetics Fall 2011
Final Exam Genetics Fall 2011

... 47) In a certain breed of dog, the alleles B and b determine black and brown coats respectively. However, the allele Q of a gene on a separate chromosome is epistatic to the B and b color alleles resulting in a gray coat (q has no effect on color). If animals of genotype B/b ; Q/q are intercrossed, ...
3.1 Chromosome Number in Different Species
3.1 Chromosome Number in Different Species

... An extra X chromosome also has fewer deleterious effects than an extra autosome. This is because, in mammals, all X chromosomes except one are inactivated very early in embryonic development. If this were not the case, then females would have twice as many active Xlinked genes as males, and would th ...
Y chromosome
Y chromosome

...  Alfred Sturtevant, one of Morgan’s students, constructed a genetic map, an ordered list of the genetic loci along a particular chromosome  Sturtevant predicted that the farther apart two genes are, the higher the probability that a crossover will occur between them and therefore the higher the ...
Human Genetics: Bug Karyotype Ch. 14
Human Genetics: Bug Karyotype Ch. 14

... 1. How many total chromosomes are present in a normal bug karyotype? _____________ 2. How many chromosomes are present in each cell of a human? _____________ 4. Chromosomes that are NOT sex chromosomes are called autosomes. How many total autosomes are present in a bug’s normal karyotype? __________ ...
Karyotype and Pedigree Notes
Karyotype and Pedigree Notes

... ____________________________________3. Why is Lanny’s (III-3) genotype X?Y? ____________________________________ 4. Why is Bambi’s (IV-1) genotype X?XI? 5. Without genetic testing, what is one way that we might know Bambi’s genotype? ____________________________________ 6.If a female is colorblind, ...
mutations - Sites@UCI
mutations - Sites@UCI

... What Causes Mutations?  There are two ways in which DNA can become mutated:  Mutations can be inherited.  Parent to child ...
Bio 130 – Quiz April 4
Bio 130 – Quiz April 4

... A. This mutation occurs in all offspring of a male with the mutation. B. This mutation occurs in all male but no female offspring of a male with the mutation. C. This mutation occurs in all offspring of a female with the mutation. D. This mutation occurs in all male but no female offspring of a fema ...
Chapter 5.3 – Human Genetics (Part I)
Chapter 5.3 – Human Genetics (Part I)

...  How can identical twins have the same genes but not look the same? Environmental influences can affect the appearance of identical twins – Nutrition and Horomones ...
SBI3U 5.1 5.2 Quiz Review
SBI3U 5.1 5.2 Quiz Review

... 5. Gametes, either egg or sperm, are ___ which means they contain only one copy of each type of chromosome that the diploid parent cell contains. • Haploid ...
10.1 MEIOSIS
10.1 MEIOSIS

... ▫ Haploid Cells: only have 1 of each kind of chromosome n  Found ONLY IN SEX CELLS (sperm and egg)  Sex cells also known as gametes ...
1 - Webcourse
1 - Webcourse

... 8. The mother of a family of 10 children has blood type Rh+. She also has a very rare condition, elliptocytosis, with no adverse clinical effect, in which the red blood cells are oval rather than round. The father is Rh- and has normal red cells. Their children include 1 Rh+ child with normal blood ...
GENETICS A
GENETICS A

... therefore NO true breeding pink flowering plants. • Codominance: both alleles equally expressed. Human blood type, cow coloring ...
Fuggles
Fuggles

... Many people mistakenly believe that a dominant allele (“T” in the tail shape example) is the most prevalent form or that the dominant allele can switch off or mask the recessive allele. Actually, all dominance refers to is what the heterozygous combination codes for. If it codes for one of the homoz ...
Mutation Notes
Mutation Notes

... ►A point mutation is a change in a single base pair in DNA.  A change in a single nitrogenous base can change the entire structure of a protein because a change in a single amino acid can affect the shape of the protein. ...
Lecture 5a
Lecture 5a

... What does that show? ...
Karyotyping
Karyotyping

... are similar in size, shape, and the position of their centromere. In humans, 22 homologous pairs of chromosomes are called autosomes. The twenty-third pair, which determines the individual’s sex, make up the sex chromosomes. Females have only one type of sex chromosome, which is called an X chromoso ...
Introducing:
Introducing:

... gene map. It is called a map because it shows where the genes are located down the chromosome. Genes have numbers and letters that make up their names. •You can see how any rearrangement mutations in the chromosomes can alter the order and/or function of gene. •Numerical mutations will affect the nu ...
Model Organisms pre-class activity: Huntington disease
Model Organisms pre-class activity: Huntington disease

... If a father has between 27 and 35 repeats in his gene, this chromosome can gain repeats when the sperm enters the egg and begins to form an embryo. If this chromosome ends up with more than 40 repeats, the child will develop the disease. 6. (a) Draw a Punnett square showing a cross between an unaffe ...
Q1. In humans, the sex chromosomes X and Y determine whether
Q1. In humans, the sex chromosomes X and Y determine whether

... idea that twins have come from one (fertilised) egg idea that Y sperm / Y chromosome produces boys each for 1 mark allow 1 mark if candidate selects A and states that Y sperm / Y chromosome produce boys (reject Y gene unqualified) OR allow 1 mark if candidate selects C and states that twins must hav ...
N.S. 100 Lecture 15 - PPT Evolution Spring 2009 Assignment Page
N.S. 100 Lecture 15 - PPT Evolution Spring 2009 Assignment Page

... Specific breeds of dog result if dogs are only allowed to breed with others in the same breed ...
Lecture 8
Lecture 8

... chromosome, the observed recombination frequency approaches, but doesn’t exceed 50% for two genes on the same chromosome. 50% recombination is the same value that is observed for two independently assorting genes on different chromosomes. ...
Chapter 7 Note taking Form
Chapter 7 Note taking Form

... Expression of sex-linked genes is similar to _________________________ genes in females. X chromosome inactivation randomly _______________________ one X chromosome. ...
Inheritance Patterns - Bergen County Technical Schools
Inheritance Patterns - Bergen County Technical Schools

... Found on Chromosome 12 ...
Sex-Linkage (X-Linked Traits)
Sex-Linkage (X-Linked Traits)

... have the condition, but a male will have a more severe form because he has no other X chromosome to offset it ...
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Skewed X-inactivation

Skewed X chromosome inactivation occurs when the inactivation of one X chromosome is favored over the other, leading to an uneven number of cells with each chromosome inactivated. It is usually defined as one allele being found on the active X chromosome in over 75% of cells, and extreme skewing is when over 90% of cells have inactivated the same X chromosome. It can be caused by primary nonrandom inactivation, either by chance due to a small cell pool or directed by genes, or caused by secondary nonrandom inactivation, which occurs by selection. Most females will have some levels of skewing. It is relatively common in adult females; around 35% of women have skewed ratio over 70:30, and 7% of women have an extreme skewed ratio of over 90:10. This is of medical significance due to the potential for the expression of disease genes present on the X chromosome that are normally not expressed due to random X inactivation. X chromosome inactivation occurs in females to provide dosage compensation between the sexes. If females kept both X chromosomes active they would have twice the number of active X genes than males, who only have one copy of the X chromosome. At approximately the time of implantation (see Implantation (human embryo), one of the two X chromosomes is randomly selected for inactivation. The cell undergoes transcriptional and epigenetic changes to ensure this inactivation is permanent. All progeny from these initial cells will maintain the inactivation of the same chromosome, resulting in a mosaic pattern of cells in females.
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