Term
| What function does profilin serve in cell cytoskeleton? |
|
Definition
| Causes the actin monomers to be added faster, thus pushing the overall process towards filament growth |
|
|
Term
| What function does thymosin serve in cell cytoskeleton? |
|
Definition
| Causes the actin monomers to be added slower, thus pushing the overall process towards filament shortening |
|
|
Term
| What function do the ARP proteins have in cell cytoskeleton? |
|
Definition
| They are the nucleating proteins for actin microfilament growth |
|
|
Term
| What functions do actin microfilaments serve in the cell and/or body? |
|
Definition
Platelet activation
Microvilli in intestinal epithelium
Movement of cells and organelles (esp neutrophils) |
|
|
Term
| What functions do actin microfilaments serve in the cell and/or body? |
|
Definition
Platelet activation
Microvilli in intestinal epithelium
Movement of cells and organelles (esp neutrophils) |
|
|
Term
| Describe the process of platelet activation? |
|
Definition
1. Signal causes an influx of Ca2+ ions into platelet
2. Actin normally capped by capping protein. Any severed filament is inactivated by gelsolin.
3. Ca2+ causes slow rise in PIP2, which inactivates gelsolin
4. Inactivation of gelsolin leads to rapid polymerization of actin microfilaments, which allows platelet to spread out and subsequently contract, leading to clotting (attaches to other cells, etc.) |
|
|
Term
| What is the movement of lamellipodium driven by in neutrophils? |
|
Definition
| Actin microfilament polymerization and branching |
|
|
Term
| What causes branching in actin microfilaments? |
|
Definition
|
|
Term
| What are the motor proteins for actin microfilaments? |
|
Definition
|
|
Term
| What are the motor proteins for microtubules? |
|
Definition
|
|
Term
| Describe the process of muscle contraction (actin and myosin) |
|
Definition
1. Myosin is attached to actin filament
2. ATP binding of myosin head group causes dissociation between actin and myosin.
3. Hydrolysis of ATP on myosin causes "cocking" of head group
4. Head group weakly binds to new site on actin filament. This causes release of the bound ADP
5. Release of bound ADP causes myosin to return to original shape (in step 1), which moves the two filaments relative to one another
6. Steps #1-5 repeat |
|
|
Term
| What type of myosin is involved in muscle contraction? What are these arrangements commonly referred to as? |
|
Definition
| Myosin II. Thick filaments |
|
|
Term
| What is the role of titin? |
|
Definition
| It acts as a spring for the sarcomere. They attach to the myosin filaments. |
|
|
Term
| What are the functions of Cap Z and tropomodulin in the sarcomere? |
|
Definition
| They cap the ends of the myosin filaments. |
|
|
Term
| What is the role of tropomyosin and troponin in muscle contraction? |
|
Definition
| Troponin complex binds Ca2+ ions. When bound, they cause a conformation shift in the tropomyosin. Tropomyosin normally blocks the binding site for the myosin head group. when it is moved out of the way by the troponin complex, myosin can bind and muscle contraction can initiate |
|
|
Term
| What is the one major difference in cardiac muscle morphology as compared to skeletal muscle? What is this useful for? |
|
Definition
| Presence of intercalating discs, which allow for simultaneous muscle contraction between neighboring cardiac cells. |
|
|
Term
| What are two major differences between microfilaments and microtubules? |
|
Definition
1. Microtubules are comprised of dimers of alpha and beta tubulin whereas microfilaments are comprised of monomers of actin.
2. Actin is spontaneous in its polymerization, whereas microtubules require GTP (Note: actin does use ATP during muscle contraction, however) |
|
|
Term
| How are microtubules formed initially? |
|
Definition
| By gamma-tubulin initiation. Gamma-tubulin initiates the polymerization of microtubules and is located at the most minus end of the filament. |
|
|
Term
| Where are gamma tubulin proteins located in the cell? |
|
Definition
|
|
Term
| What are microtubules used for? |
|
Definition
Maintenance of cellular organization
Movement of vesicle/organelles
Movement of chromosomes (mitosis/meiosis)
Movement of cells |
|
|
Term
| How are Kinesins and Dyneins different? |
|
Definition
Kinesin binds to vesicle destined for cell membrane. They are (+) directed (go towards the plus end of microtubule)
Dynein binds to vesicles destined for organelles/nucleus. They are (-) directed (go towards the minus end of microtubule) |
|
|
Term
| What organelle will deteriorate first if there is a problem with microtubule polymerization? |
|
Definition
| Golgi (it is known as a "wandering" organelle and must constantly be maintained by microtubules) |
|
|
Term
| What causes the movement of cilia? |
|
Definition
| Action of dynein cross links in the cilium microtubules. |
|
|
Term
| What are the major differences between primary cilia and motile cilia? |
|
Definition
Primary do not have central microtubules and the microtubules are not cross linked.
Motile cilia have central microtubules and the microtubules are cross linked by dynein.
Motile cilia are used for locomotion, whereas primary cilia are used for transduction of signals (act like a giant antennae) |
|
|
Term
| Why are intermediate filaments so stable? |
|
Definition
| They self-assemble under certain conditions without ATP or GTP being required. |
|
|
Term
| What is vimentin? How is it important diagnostically? |
|
Definition
| It is an intermediate filament protein. Vimentin is very important marker for pathologists who are looking for cancerous tissues. Cells outside mesenchyme cells that express vimentin are often cancerous. |
|
|
Term
| What are the primary regulators of mitosis? |
|
Definition
| cyclinA-Cdk2 and cyclin B-Cdk1 complexes |
|
|
Term
| What occurs molecularly at the metaphase-anaphase transition? |
|
Definition
| Activation of APC and destruction of cyclinB |
|
|
Term
| What happens to the Golgi body during mitosis? |
|
Definition
| It is broken into smaller pieces and divided between the two daughter cells through the activation of cyclinB. CyclinB prevents reformation of the Golgi body, which leads to its fracture into smaller parts. |
|
|
Term
| What happens to the nuclear envelope during mitosis? |
|
Definition
| Lamins are phosphorylated by cyclinB. This causes them to dissociate and the overall effect of the dissolution of the nuclear envelope |
|
|
Term
| Regarding microtubule growth and shortening: What is the main determinant of whether a filament will grow or shrink? |
|
Definition
| Presence of a GTP cap on the (+)-end will lead to growth. Presence of a GDP cap on the (+)-end will lead to shrinking. |
|
|
Term
| Why does GDP-bound tubulin lead to shrinking of the microtubule? |
|
Definition
| GTP-bound tubulin creates a straight molecule, whereas GDP-bound tubulin bends. This bending action makes the tubulin dimer susceptible to cleavage |
|
|
Term
| Regarding mitosis, when do centrosomes duplicate? |
|
Definition
|
|
Term
| What are the different types of microtubules involved in the mitotic spindle? |
|
Definition
1. Astral (go out from centrioles but do not encounter microtubules from other centriole)
2. Kinetochore (attach to kinetochore)
3. Overlap (interact with microtubules from other centriole and connect, stabilizing the overall mitotic spindle) |
|
|
Term
| What is the role of condensin in mitosis? |
|
Definition
| Condenses chromosomes (uses A LOT of ATP) |
|
|
Term
| what is the role of cohesin in mitosis? |
|
Definition
| Acts as the "glue" between sister chromatids. Gets separated by separase during anaphase |
|
|
Term
| What are the steps in the separation of sister chromosomes during anaphase? |
|
Definition
1. APC destroys CyclinB and ubiquinates securin
2. Securin destruction releases separase
3. Separase cleaves bonds between sister chromatids (between neighboring cohesins). |
|
|
Term
| How do the sister chromatids reach their respective spindle poles during anaphase? |
|
Definition
| They "walk" towards them (exact mechanism not known yet) |
|
|
Term
| What occurs during anaphase regarding the spindle microtubules? |
|
Definition
Overlap microtubules have kinesins that push against one another and push the two poles apart (also makes the overall cell oval shaped).
Dyneins on the astral microtubules pull the poles towards the edges of the cell (further exacerbate the effect of the overlap microtubules) |
|
|
Term
| What is the name of the structure that connects the homologs during meiosis? |
|
Definition
|
|
Term
| What are the steps in recombination during meiosis? |
|
Definition
1. Double-strand breaks are made ON PURPOSE on the paired chromosomes by Spo11 (related to topoisomerases)
2. The homolog strand "invades" the broken region and is used as the template for the repair (forms Holliday junction)
3. The result of the Holliday junction are chiasma
4. During anaphase I the cohesins on the arms of the homologous chromosomes are broken, and the chiasma separate, leading to fully recombined chromosomes. |
|
|
Term
| What are the two main contributors to genetic diversity in germ cells? |
|
Definition
| Independent assortment of homologs and recombination between homologs during meiosis |
|
|
Term
| How do the sex chromosomes arrange in meiosis in male germ cells (have XY to account for) |
|
Definition
| The X and Y chromosomes pair with each at a “pseudoautosomal” region at one end of each chromosome |
|
|
Term
| What is the proposed function of the cytoplasmic bridges in spermatogenesis? |
|
Definition
| Important for ensuring that spermatids formed have viable genes (are properly haploid). The cytoplasmic bridges allows for proteins to flow between the 8 spermatids. |
|
|
Term
| When does nondisjunction normally occur? |
|
Definition
|
|
Term
| What is the strongest risk factor for aneuploidy? |
|
Definition
|
|
Term
| What is the proposed explanation for why maternal age increases the risk of nondisjunction (and therefore fetal aneuploidy)? |
|
Definition
| Weakened cohesins within homologs in the primary oocytes of older women that leads to nondisjunction during anaphase I |
|
|
Term
| Explain the process of sex determination |
|
Definition
1. SRY gene on the Y chromosome causes Testes Determining Factor (TDF) genes to be expressed.
2. TDF genes lead to the formation of testes
3. Leydig cells produce testosterone
4. Sertoli cells produce anti-mullerian hormone, which blocks the formation of female internal genitalia. |
|
|
Term
| How is SOX9 activated and what does it do? |
|
Definition
| It is activated by SRY gene on the Y chromosome. It induces production of anti-mullerian hormone (Amh) |
|
|
Term
| Explain the process of X chromosome inactivation. What is the final product? |
|
Definition
1. XIST gene expressed on X chromosome codes for XIST RNA, which "paints" the X chromosome, inactivating it.
Barr body is the result of this process
Note: The silenced X chromosome is never completely silenced, just greatly inhibited. |
|
|
Term
| What is a reciprocal chromosome translocation? What can it lead to? |
|
Definition
| It is an exchange of parts of one chromosome to the other (non homologous chromosomes). This leads to balanced genetic makeup, however may result in over-expression or under-expression of certain genes and/or infertility (due to nondisjunction during meiosis) |
|
|
Term
| What is a Robertsonian chromosome translocation? |
|
Definition
Translocation in one of the 5 acrocentric (unbalanced regarding the centromere) chromosomes (13, 14, 15, 21, 22).
Can be balanced and cause no health effects
Can be unbalanced and lead to deletion of fragment (note: this is another method to get Down's syndrome). |
|
|
Term
| What are the characteristics of autosomal dominant inheritance? |
|
Definition
1. No skipped generations
2. Males and females equally likely to be affected
3. Affected individuals ALWAYS have an affected parent
4. Unaffected individuals never pass trait to offspring |
|
|
Term
| What accounts for the continued presence of autosomal dominant disorders? |
|
Definition
1. VARIABLE EXPRESSIVITY/PLEIOTROPY
2. LATE ONSET
3. HIGH RECURRENT MUTATION RATE
4. INCOMPLETE PENETRANCE |
|
|
Term
|
Definition
The genetic effect a single gene can have on many phenotypes.
One explanation would be that the gene product targets different cell types, such as signaling factors. |
|
|
Term
| What is genetic anticipation? |
|
Definition
| Seen in trinucleotide repeat disorders (such as Myotonic Dystrophy and Huntington's disease). The disease gets worse with each generation of affected individuals and the age of onset decreases. |
|
|
Term
| How does incomplete penetrance and variable expressivity differ? |
|
Definition
In diseases with variable expressivity the patient always expresses some of the symptoms of the disease and varies from very mildly affected to very severely affected.
In incomplete penetrance, the individual either expresses the trait or not. This is really only seen with dominant conditions. |
|
|
Term
| What are the characteristics of autosomal recessive disorders? |
|
Definition
1. Males and females are equally likely to be affected.
2. On average, the recurrence risk to the unborn sibling of an affected individual is 1/4.
3. The trait is characteristically found in siblings, not parents of affected or the offspring of affected.
4. Parents of affected children may be related. The rarer the trait in the general population, the more likely a consanguineous mating is involved.
5. The trait may appear as an isolated (sporadic) event in small sibships. |
|
|
Term
| What are the characteristics of X-linked disorders? |
|
Definition
1. X-linked genes are never passed from father to son. A female child always gets the father's X chromosome and one of the two X's of the mother.
2. An affected female must have an affected father. Males are always hemizygous for X linked traits, that is, they can never be heterozygotes or homozygotes.
3. Males are never carriers. A single dose of a mutant allele will produce a mutant phenotype in the male, whether the mutation is dominant or recessive. On the other hand, females must be either homozygous for the normal allele, heterozygous, or homozygous for the mutant allele, just as they are for autosomal loci. |
|
|
Term
| What do you generally look for in determining if a trait is X-linked dominant on a family pedigree? |
|
Definition
| The key for determining if a dominant trait is X-linked or autosomal is to look at the offspring of the mating of an affected male and a normal female. If the affected male has an affected son, then the disease is not X-linked. All of his daughters must also be affected if the disease is X-linked. In this pedigree, all of these conditions are met. |
|
|
Term
| How does the concordance value determine whether a trait is heritable or not? |
|
Definition
| Traits that are largely determined by genes result in a heritability estimate that approaches 1.0 (i.e., cMZ approaches 1.0, and cDZ approaches 0.5). As the difference between MZ and DZ concordance rates becomes smaller, heritability approaches zero. |
|
|
Term
| What are the characteristics to mitochondrial diseases |
|
Definition
1. Mitochondria are ONLY inherited from the mother (sperm leave mitochondria behind during fertilization).
2. A female with a mitochondrial trait will give it to ALL her daughters, while a male will not give trait to any of his offspring.
3. There is only 1 allele so there is no issue of dominance.
4. Mutation rate of mtDNA is 10 times higher than nuclear DNA. |
|
|
Term
| What is the LOD score used for? |
|
Definition
Conventionally, a LOD score of 3.0 or more is accepted as evidence of linkage; a score of 3.0 indicates that the likelihood for linkage is 1000 times greater than the likelihood against linkage.
Conversely, a LOD score lower than -2.0 (odds of 100 to 1 against linkage) is considered to be evidence that two loci are not linked. |
|
|
Term
| What are the pro-apoptotic molecules that mitochondria can release? |
|
Definition
Cyt C
Pro-caspases
AIF
SMAC/Diablo
Endo G |
|
|
Term
| What are three proposed explanations for the presence of mitochondrial disorders in the population? |
|
Definition
1. MtDNA polymerase is error prone
2. Mitochondria lack repair mechanisms
3. Mitochondria generate ROS |
|
|
Term
| What does ADP ribosylation usually do? |
|
Definition
Inactivates the target protein.
Mono-ADP-ribotransferases transfer ADP ribose from NAD+ to a target protein. |
|
|
Term
| What is the function of ADP-ribosylhydrolases? |
|
Definition
| ADP-ribosylhydrolase cleaves the ADP ribose from the target protein and therefore reactivate it. |
|
|
Term
| What molecule is required for ribosylation? |
|
Definition
|
|
Term
| Ribosylation always occurs on a specific (1) on the target protein? |
|
Definition
|
|
Term
| What is the overall molecular formula for ribosylation? |
|
Definition
NAD+ + Arginine residue (on target protein) -->
nicotinamide + ribosylated protein |
|
|
Term
| What enzymes are responsible for transfer of ADP from NAD+ to the target protein in ribosylation? |
|
Definition
| ADPRTs (ADP Ribosyltransferases) |
|
|
Term
| What enzymes are responsible for restoring function to the protein following ribosylation? |
|
Definition
| ADP ribosylhydrolases. Note: the end product is protein and ADP ribose. |
|
|
Term
| What does cyclic ADP ribose (cADPR) do? |
|
Definition
| Regulates release of inositol triphosphate and Ca2+ release from the ER (or sarcoplasmic reticulum if muscle cell) |
|
|
Term
| What are the functions of poly ADP ribosylation? |
|
Definition
1. Recruitment of DNA repair enzymes
2. Essential component of cell death pathways; release of apoptosis inducing factor.
3. Surveillance factor of genome integrity. |
|
|
Term
|
Definition
| Cytokines are soluble (glyco)proteins, non-immunoglobulin in nature, released by living cells of the host, which act at pico- to nanomolar concentrations through specific receptors to regulate host cell function. |
|
|
Term
|
Definition
| Cytokines produced by monocytes |
|
|
Term
|
Definition
Cytokines produced by activated T cells
Ex: Macrophage activating factor (MAF), histamine releasing factor (HAF) |
|
|
Term
|
Definition
Cytokines produced by leukocytes that act on other leukocytes.
e.g. IL-1 to IL-15 |
|
|
Term
|
Definition
| Cytokines that control viral propagation/infection and help the immune response. e.g. INF-a to w |
|
|
Term
| What are Colony-Stimulating Factors? |
|
Definition
| Cytokines so as to promote the maturation of leukocytes. e.g. granulocyte, G-CSF, macrophage, M-CSF |
|
|
Term
|
Definition
| Cytokines that stimulate the migration of leukocytes during immune responses. e.g. lymphotactin. |
|
|
Term
|
Definition
| Cytokines involved in stem cell differentiation and other functions |
|
|
Term
| What is the main function of the inflammatory response? |
|
Definition
| To bring fluid, proteins, and cells from the blood into the damaged tissues. |
|
|
Term
| What is the function of PGE2? |
|
Definition
| Febrile response (producing a fever) |
|
|
Term
| What is the function of TXA2? |
|
Definition
Vasoconstriction
It is a derivative of arachidonic acid |
|
|
Term
| What are the functions of Prostaglandins (PGs) |
|
Definition
Vasodilation, increased vascular permeability
They are products of arachidonic acid |
|
|
Term
| What are the functions of leukotrienes (LTs)? |
|
Definition
contraction of smooth muscle, increased vascular permeability, and chemotaxis of phagocytes
They are products of arachidonic acid |
|
|
Term
| What are adipokines and what produces them? |
|
Definition
| Adipokines are released from adipocytes. Evidence that they lead to a chronic subinflammatory state that could play a central role in the development of insulin resistance and type 2 diabetes, and the increased risk of cardiovascular disease associated with obesity |
|
|
Term
| What is the autoimmune disease that is characterized by antibodies against the Acetylcholine Receptor, muscle weakness and fatigue? |
|
Definition
|
|
Term
| What are the characteristics of Myasthenia Gravis? |
|
Definition
| An autoimmune disease that is characterized by antibodies against the Acetylcholine Receptor, muscle weakness and fatigue |
|
|
Term
| What is the disease characterized by situs inversus with associated problems with sinusitis/bronchitis and male infertility? Why does this happen? |
|
Definition
| Kartagener's Syndrome. This occurs due to a ciliary motor defect. The situs inversus results because the normal arrangement of organs in the developing embryo is dictated by the direction of beating cilia. Without it, the organs develop on the wrong side 50% of the time. |
|
|
Term
| Describe Kartagener's Syndrome |
|
Definition
| A disease characterized by situs inversus with associated problems with sinusitis/bronchitis and male infertility. This is due to problems in ciliary movement |
|
|
Term
| What is Epidermolysis Bullosa Simplex? |
|
Definition
| A defect in intermediate filaments (keratins) in skin epithelia that results in drastic skin lesions. |
|
|
Term
| What is the disease characterized by a defect in intermediate filaments (keratins) in skin epithelia that results in drastic skin lesions? |
|
Definition
| Epidermolysis Bullosa Simplex |
|
|
Term
|
Definition
| Trisomy 21. Incidence rises with maternal age. Characterized by mild-moderate MR, increased risk of leukemia, heart defects and AD (because amyloid beta gene is on chromosome 21). Epicanthal folds over eyes (however not diagnostic). Brushfield spots in the iris is diagnostic |
|
|
Term
| Trisomy 21 and Brushfield spots |
|
Definition
|
|
Term
| Trisomy 13 with polydactyly, small or absent eyes, microcephaly, cleft palate, omphalocele, MR, and early death |
|
Definition
|
|
Term
|
Definition
| Trisomy 13 with polydactyly, small or absent eyes, microcephaly, cleft palate, omphalocele, MR, and early death |
|
|
Term
| Trisomy 18, MR, microcephaly, small eyes, clenched hands, coloboma of iris (split in iris--looks like reptilian eye), and early death |
|
Definition
|
|
Term
| Describe Edwards Syndrome |
|
Definition
| Trisomy 18, MR, microcephaly, small eyes, clenched hands, coloboma of iris (split in iris--looks like reptilian eye), and early death |
|
|
Term
| 47 XXY. Gynecomastia due to low testosterone levels, reduced facial and body hair, female fat distribution, and infertility |
|
Definition
|
|
Term
| Describe Klinefelter Syndrome |
|
Definition
| 47 XXY. Gynecomastia due to low testosterone levels, reduced facial and body hair, female fat distribution, and infertility |
|
|
Term
| 45 X0 (monosomy X). Characterized by webbed neck caused by abnormal formation of lymphatics in the neck, "shield chest", puffiness or swelling of the hands and feet, "streak" ovaries w/ associated infertility |
|
Definition
|
|
Term
|
Definition
| 45 X0 (monosomy X). Characterized by webbed neck caused by abnormal formation of lymphatics in the neck, "shield chest", puffiness or swelling of the hands and feet, "streak" ovaries w/ associated infertility |
|
|
Term
| Genetic defect caused by deletion of genes from long arm of chromosome 7, including the elastin gene. Characterized by MR, teeth abnormalities. (Note: Think of Jimmy) |
|
Definition
|
|
Term
| Describe William's Syndrome |
|
Definition
| Genetic defect caused by deletion of genes from long arm of chromosome 7, including the elastin gene. Characterized by MR, teeth abnormalities. (Note: Think of Jimmy) |
|
|
Term
| Disease characterized by deletion of the short arm of chromosome 5. Characteristic cry that sounds like a cat, caused by abnormal larynx development. Resembles down syndrome in the physical characteristics. |
|
Definition
|
|
Term
| Describe Cri Du Chat Syndrome |
|
Definition
| Disease characterized by deletion of the short arm of chromosome 5. Characteristic cry that sounds like a cat, caused by abnormal larynx development. Resembles down syndrome in the physical characteristics. |
|
|
Term
| How do Prader-Willi and Angelman Syndromes differ? |
|
Definition
| Both are caused by a deletion on chromosome 15. Prader-Willi is only seen in males with a defective paternal chromosome 15 (maternal copy is imprinted in males). If maternal copy is defective, it will not cause disease IF THE CHILD IS MALE. Angelman Syndrome is seen in females and is caused by defective maternal chromosome 15 (paternal copy is imprinted in females). If the paternal copy is defective, it will not cause disease IF THE CHILD IS FEMALE. |
|
|
Term
| Disease characterized by deletion of part of paternal chromosome 15. Only seen in males. Symptoms are short stature, hypotonia, MR, small hands and feet, and obesity. |
|
Definition
|
|
Term
| Describe Prader-Willi Syndrome |
|
Definition
| Disease characterized by deletion of part of chromosome 15. Only seen in males. Symptoms are short stature, hypotonia, MR, small hands and feet, and obesity. |
|
|
Term
| Disease characterized by deletion of part of maternal chromosome 15. Only seen in females. Symptoms are severe MR, seizures, ataxic gait |
|
Definition
|
|
Term
| Describe Angelman Syndrome |
|
Definition
| Disease characterized by deletion of part of maternal chromosome 15. Only seen in females. Symptoms are severe MR, seizures, ataxic gait |
|
|
Term
| Disease characterized by a defect in the NF1 gene that codes for neurofibromin (tumor suppressor protein). Symptoms include presence of neural tumors. This disease has great variable expressivity |
|
Definition
| Neurofibromatoses: Neurofibromatosis type 1 (NF1) and Neurofibromatosis type 2 (NF2) |
|
|
Term
| Describe neurofibromatosis |
|
Definition
| Disease characterized by a defect in the NF1 gene that codes for neurofibromin (tumor suppressor protein). Symptoms include presence of neural tumors. This disease has great variable expressivity |
|
|
Term
|
Definition
| Pleiotropy occurs when one gene influences multiple phenotypic traits |
|
|
Term
| Disease characterized by trinucleotide CAG (coding for glutamine) repeats that causes a gain-of-function to protein (1) that is used in transport of neurotrophic factor vesicles in neurons. The gain-of-function makes it bind tightly to the accessory proteins, thus preventing the vesicles from being transported. Symptoms are depression (early stages), chorea movements and psychiatric changes. |
|
Definition
| Huntington's disease. Protein is Huntingtin |
|
|
Term
| Autosomal dominant disease characterized by trinucleotide repeats (CTG). Symptoms are progressively worsening muscle weakness and myotonia (slow relaxation of the muscles after contraction) |
|
Definition
|
|
Term
| Describe myotonic dystrophy |
|
Definition
| Autosomal dominant disease characterized by trinucleotide repeats (CTG). Symptoms are progressively worsening muscle weakness and myotonia (slow relaxation of the muscles after contraction) |
|
|
Term
| Describe Huntington's Disease |
|
Definition
| Autosomal dominant disease characterized by trinucleotide CAG (coding for glutamine) repeats that causes a gain-of-function to protein (1) that is used in transport of neurotrophic factor vesicles in neurons. The gain-of-function makes it bind tightly to the accessory proteins, thus preventing the vesicles from being transported. Symptoms are depression (early stages), chorea movements and psychiatric changes. |
|
|
Term
| An X-linked dominant disorder that is the most common form of inherited mental retardation. Associated with increased CGG repeats in the FMR1 gene (necessary for proper brain development). Symptoms include autistic tendencies and abnormally large testicles in males. |
|
Definition
|
|
Term
| Describe Fragile X syndrome |
|
Definition
| An X-linked dominant disorder that is the most common form of inherited mental retardation. Associated with increased CGG repeats in the FMR1 gene (necessary for proper brain development). Symptoms include autistic tendencies and abnormally large testicles in males. |
|
|
Term
| Autosomal dominant mutation in the fibroblast growth factor receptor, which causes a disorder of cartilage conversion to bone. This leas to severely shortened long bones. It is believed the condition is lethal in its homozygous form. |
|
Definition
|
|
Term
|
Definition
| Autosomal dominant mutation in the fibroblast growth factor receptor, which causes a disorder of cartilage conversion to bone. This leas to severely shortened long bones. It is believed the condition is lethal in its homozygous form. |
|
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Term
| Autosomal recessive disorder characterized by mutations in the CFTR gene that encodes the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR), which regulates Cl- transport. The secretion of Cl- into the lung, GI tract and the pancreas results in Na+ secretion and water export. Symptoms are thick mucous in the lung and fibrosis of the pancreas. |
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Definition
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Term
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Definition
| Autosomal recessive disorder characterized by mutations in the CFTR gene that encodes the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR), which regulates Cl- transport. The secretion of Cl- into the lung, GI tract and the pancreas results in Na+ secretion and water export. Symptoms are thick mucous in the lung and fibrosis of the pancreas. |
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Term
| Autosomal recessive disorder characterized by defect in the VHL gene. Characterized by pheochromacytomas, hemangiomas (especially in kidneys and adrenals), renal cell carcinoma, angiomatosis. Symptoms can be aggressiveness. |
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Definition
| von Hippel-Lindau disease (VHL) |
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Term
| Describe von Hippel-Lindau disease (VHL) |
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Definition
| Autosomal recessive disorder characterized by defect in the VHL gene. Characterized by pheochromacytomas, hemangiomas (especially in kidneys and adrenals), renal cell carcinoma, angiomatosis. Symptoms can be aggressiveness. |
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Term
| What is unique about von Hippel-Lindau Disease? |
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Definition
| Although it is autosomal recessive, its inheritance pattern is that of being autosomal dominant. This is because if you inherit one mutant copy of the gene you have an extremely likely chance of developing a second mutation in at least one other cell (recall this similarity in retinoblastoma) |
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Term
| X-linked dominant disease characterized by defect in ALA synthetase (recall that it is the first step in heme synthesis). Symptoms are an overproduction of ALA synthetase and subsequent porphyria |
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Definition
| X-linked Erythropoietic Protoporphyria |
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Term
| X-linked dominant disease characterized by defect in ALA synthetase (recall that it is the first step in heme synthesis). Symptoms are a decrease in ALA synthetase levels, resulting in decreased heme synthesis and accompanying increase in circulating iron levels |
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Definition
| X-linked Sideroblastic Anemia |
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Term
| Describe X-linked Erythropoietic Protoporphyria |
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Definition
| X-linked dominant disease characterized by defect in ALA synthetase (recall that it is the first step in heme synthesis). Symptoms are an overproduction of ALA synthetase and subsequent porphyria |
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Term
| Describe X-linked Sideroblastic Anemia |
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Definition
| X-linked dominant disease characterized by defect in ALA synthetase (recall that it is the first step in heme synthesis). Symptoms are a decrease in ALA synthetase levels, resulting in decreased heme synthesis and accompanying increase in circulating iron levels |
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Term
| X-linked recessive disease characterized by a deficiency in a critical protein (1) that is involved in the production of NADPH. Symptoms are anemia and jaundice (the latter if the hemolytic crisis is severe). |
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Definition
| Glucose 6 phosphate dehydrogenase deficiency (G6PD deficiency) |
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Term
| Describe Glucose-6-phosphate Dehydrogenase Deficiency (G6PD deficiency) |
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Definition
| X-linked recessive disease characterized by a deficiency in a critical protein (1) that is involved in the production of NADPH. Symptoms are anemia and jaundice (the latter if the hemolytic crisis is severe). |
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Term
| X-linked recessive disease caused by a defective gene for the muscular protein dystrophin. Associated with a massive elevation of creatine kinase levels in the blood. |
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Definition
| Duchenne Muscular Dystrophy |
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Term
| Describe Duchenne Muscular Dystrophy |
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Definition
| X-linked recessive disease caused by a defective gene for the muscular protein dystrophin. Associated with a massive elevation of creatine kinase levels in the blood. |
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Term
| X-linked recessive disease caused by a mutation in alpha-galactosidase A. Symptoms include angiokeratomas (small painless purple lesions on buttocks, thighs, and umbilicus), extremity pains, GI disorders. The mosaicism in women may account for why some women are essentially asymptomatic while others have severe disease |
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Definition
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Term
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Definition
| X-linked recessive disease caused by a mutation in alpha-galactosidase A. Symptoms include angiokeratomas (small painless purple lesions on buttocks, thighs, and umbilicus), extremity pains, GI disorders. The mosaicism in women may account for why some women are essentially asymptomatic while others have severe disease |
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Term
| X-linked recessive disease in the beta-hexosaminidase A enzyme (recall that it cleaves GM2 ganglioside). It's severity depends on the type of mutation that results in enzyme inactivity: missense would be less severe than frameshift, for example. Symptoms are progressively worsening neurodegeneration |
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Definition
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Term
| Describe Tay Sachs Disease |
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Definition
| X-linked recessive disease in the beta-hexosaminidase A enzyme (recall that it cleaves GM2 ganglioside). It's severity depends on the type of mutation that results in enzyme inactivity: missense would be less severe than frameshift, for example. Symptoms are progressively worsening neurodegeneration |
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