Term
| What are the types of genetic defects? |
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Definition
single gene defect multifactorial defect (combination of multiple genes) chromosomal defect (can be visualized - cytogenetics) inherited genetic defect (may occur during meiosis somatic cell genetic defect (change in somatic cell, not transmitted to offspring)
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Term
| Which diseases result from the deletion of an entire structural gene? |
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Definition
Hemophilia- entire factor VIII gene is removed β-Thalassemia- severity depends on # of genes deleted. major: lethal. Both β globin genes mutated. minor: mild. One β globin mutated. Microcytic anemia |
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Term
| What are examples of partial deletion of gene? |
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Definition
Duchenne muscular distrophy: cause by "out of frame" deletion. More severe. Becker muscular distrophy: "in frame deletion"(multiple of 3). less severe. Can also be caused by partial gene Duplication of specific exons. |
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Term
| What diseases are a result of insertion or amplification of DNA sequences? |
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Definition
Lead to big increase in tri-nucleotide repeats. Fragile X (FMR-1)gene
Myotonic Dystrophy (DMPK)
HuntingtonÕs (HD) |
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Term
| What is Microsatillite Instability and how do oyou test for it? |
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Definition
MSI is due to a defective MMR gene in certain cancers. (13% of colorectal, gastric, and endometrial. PCR test |
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Term
| Insertion of Alu sequences with in a gene. |
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Definition
Alu sequences rememble 75L RNA Transcribe by RNA polemerase II but are not translated. about 5-10% of genome Called mobile or "jumping" Alu elements and can be lethal. Can interupt reading frame.
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Term
| What causes Cystic Fibrosis and how do you test for it? |
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Definition
Codon Deletion lose ΔPhe 508 which is a cystic fibrosis transmembrane regulator (CFTR) In frame shift PCR test |
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Term
| A point mutation at a proteolytic cleavage site leads to... |
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Definition
Loss of phosphorylation sites. TCC(Ser)→ GCC(Ala) |
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Term
| What test do you use to identify family members? |
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Definition
Southern blot Blots for Microsatillites/Short Tandem Repeats |
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Term
| What type of mutation happens in Ehlers-Danlos Syndrome? |
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Definition
Loss of exon 6 in COL1A2 gene COL1A2 gene codes for α-2 chain of procollagen. Leads to hypermobility of the joints
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Term
| Poly-Adenylation Site Mutation |
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Definition
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Term
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Definition
Arg 506 Gln mutation→ loss of proteolytic cleavage site. Prevents inactivation of Va. Activated Protein C resistance (APC-resistance) Heterozygotes are more susceptable to thrombosis. Associated with 90% of deep venous thrombosis (DVT)
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Term
| Why do Aminoglycoside anitbiotics lead to deafness in some people? |
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Definition
Mutation in 12S RNA(mitochondria) Makes the mitochondrial RNA more similiar to bacteria. |
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Term
| What happens if you get a mutation in the mitochondria tRNA leu? |
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Definition
Effects translational system. Leads to stroke. (somthing about age) |
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Term
| Whats an example of a beneficial point mutation? |
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Definition
Alipoprotein A-1 Milano gene mutation. Low level of HDL and decreased risk of atherosclerosis. |
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Term
| How can tumor supressor genes be silenced? |
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Definition
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Term
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Definition
Post zygotic mutations produce different cell lines The same gene has different chromosomes or different mutations depending on the cell. The more abnormal cells= the more mosaicism
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Term
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Definition
Chromosomal Defect Any multiple of the haploid number of chromosomes. Common in spontaneous abortions. |
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Term
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Definition
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Term
| What is the survival rate of the different Aneuploidies? |
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Definition
trisomy 16: aborted trisomy 13(Patau): few months trisomy 18(Edwards): few months trisomy 21(Down's): long life
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Term
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Definition
Uniparental Disomy: Both copies of a single chromosome is inherited by a single parent. Can lead to getting a autosomal reccesive disease from one parent.(like cystic fibrosis) Mutations to genes located on Y chromosome.
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Term
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Definition
| A specific region of a Chromosome has been deleted. |
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Term
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Definition
| Stretched out/almost missing chromosome |
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Term
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Definition
| One chromosome inserts parts of it's chromosome into another one. |
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Term
Chromosomal Translocation |
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Definition
| 2 different chromosomes swap some information |
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Term
| Genes involved in cancer. |
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Definition
Ligase IV BRCA1/BRCA2 RAD Ku/DNA-PK ATM
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Term
| What test is used to detect Chromosomal aberrations? |
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Definition
FISH Fluoresense In Situ Hybridization |
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Term
| Besides Southern Blot, what technique could you use to detect differences in tandem repeats? |
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Definition
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Term
| What test is used to detect sickle cell anemia? |
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Definition
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