Help
Options
Question
What are some of the phenotypic features of Marfan syndrome?
click to flip
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't know
Question
What kind of disorder is Marfan? Also, what is the deficiency?
Remaining cards (51)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Catropo Gentic D/o
Genetic dosorders
| Question | Answer |
|---|---|
| What are some of the phenotypic features of Marfan syndrome? | Arachnodactyli, ectopic lens, pigeon/hollow chest, joint hypermobility, mitral valve prolapse, dissecting Aorta |
| What kind of disorder is Marfan? Also, what is the deficiency? | Marfan is AD therefore it is a structural component that is missing, namely fibrillin (a component of elastic fibers in c.t.) |
| What are two characteristics of AD disorders? | 1. A stuctural component is missing 2. It does not skip a generation |
| What are some of the phenotypic characteristics of Ehler-Danlos syndrome? | Extreme joint hyperflexibility cutanous fagility Cigarette paper skin hyperbleeding tendency (Note: sutures wont hold well in their skin) |
| What are Ehler Danlos type I and II caused by (classical Ehler Danlos)? | Mutations in the COL5A1 or COL5A2 genes that encode for the alpha chains of type 5 collagen. (Type 5 collagen stabilizes type 1 collagen) |
| What are Ehler Danlos type IV (vascular) caused by? | A Mutation in the COL3A1 gene resulting in Decreased amount of type III collagen called reticulin. |
| What do Ehler Danlos types I, II, IV most prone to? | Arterial rupture. |
| How to test for Ehler Danlos? | Patient must have present more than one of the hypermobility/flexibility maneuvers for the joints of skin. |
| What are the phenotypic characteristics of Neurofibromatosis Type 1? What are the diagnostic criteria? | 1. Axillary/inguinal freckkling 2. Cafe au Lait spots 3. Lisch nodules on the skin 4. Neurofibromas 5. Optic gliomas 6. A first degree realtive diagnosed with NF Patient must have at least two of the features to be diagnosed. |
| What is the cause of Neurofibromatosis type 1? | A mutation on Chromosome 17q resulting in a down regulation on ras-p21 resulting in benign neurofibomas (tumors) (must be excised before they turn into malignant peripheral nerve sheet tumors. |
| What are the phenotypic characteristic of Neurofibromatosis Type 2? | 1. Hearing loss (tinnitus, dizziness or imbalance) Must have two of the following: 2. Bilatera vestibular schwanoma 3. Family history of NF2 4. Meningioma, glioma, neurofibroma, schwanoma |
| What is the difference between Schwannoma vs. Neurofibroma? | Schwannomas grow around the nerve with Antoni A and Antoni B arraingements, so excision doesnt sacrifice the nerve. Neurofibromas are intertwined with the nerve so excision sacrifices the nerve. |
| What is the significance of HEreditary Hypercholesterolemia? (FH) | One of them most common Autosoma Dominant disorders, and important because of heart disease leading to early coronary heart disease and early MI. |
| What do you look for phentypically with Familial Hypercholesterolemia? | Xanthoma (yellow tumors filled withlipid-laden "foamy" histiocytes) Xanthelasma (yellow plaques usually on the eyelids filled with "foamy" histiocytes). |
| What is the underlying probem with Familial Hypercholesterolemia? | Lack of "good" LDL receptors on cells, allowing them to accumulate in the blood, because of a mutation in the LDL gene. |
| Lysosomal storage diseases are all what kind of inheritance? Why? | Autosomal recessive because they all have to do with a deficiency of an enzyme in the lysosome. |
| What is the problem with Gauchers Disease? | A mutation in the gene encoding for the Beta-glucocerebrosidease on Choromosome 1q. (Most carriers have about 50% activity of the enzyme)> |
| How does the Gaucher's patient present? Why? | With huge macrophages because of glucocerebroside accumulation expecially in the spleen, bone marrow and liver. The cytoplasm in the cells have crinkled paper/tissue paper appearance. |
| What is the more qucker way to diagnose Gaucher's Disease? | With a bone marrow aspiration and biopsy. |
| How is Gaucher's classified? | Type I (adult)- Most common and non neuronopathic. Compatible with healthy life. Common in Ashken Jews. Enlarged spleen, liver and lymph nodes, with bone skeletal problems. (Romantic fractures) Type II (infantile) & III (juvelile)Eare rare and neuropathic |
| What is the problem with Pompe (type II glycogenosis) disease? | a lysosomal alpha 1,4-glucosidase deficiency because of a mutation in chromsome 17q21-23 |
| What are the phenotypic features of Pompe? | Floppy baby syndrome, macroglossia, poor motor development, respiratory problems, failure to thrive, large QRS complexes, cardiomyopathy and cardiomegaly. Accumulation of glycogen in all lysosomes of the body. Banana shaped ventricular cavity). |
| What is the problem with Tay-Sachs (amaurotic idiocy)? | Hexoaminidase A deficency b/c of a frameshift mutation in the HexA gene on chromosome 15q . Leads to an accumulation of GM2-ganglioside (swirls). High prevalence in Ashkenazi Jews, death before age 4. (Ballooned neurons). Also note Cherry red macula. |
| Trisomy 13 | Patau syndrome |
| Trisomy 18 | Edwards syndrome |
| Trisomy 21 | Down Syndrome - maternal age effect |
| Phenotypic characteristics of Trisomy 21 | hypotonia, simmian crease, clinodactyly, epicanthal folds, upslanting eyes, open mouth, protruding tongue, opacity of pupil (brushfield spot), low set ears, depressed nasal bridge |
| Children with downs syndrome are at higher risk for: | Congenital heart defects, VSD, hypothyroidism, hearing impairment, duodenal atresia, mitral valve prolapse, Alzheimer's d/s >40yo |
| Causes of trisomy 21: | 95% --> extra chromosome 21 b/c of nondisjunction in meiosis I 2% --> b/c/ of Robertsonian translocation between Chromosome 21 and 13, 14, 15, or 22 2-3% --> Mosaic |
| How is prenatal screening done for trisomy 21? | Via Chorionic villus sampling (CVS) or amniocentesis, or ultrasound Also can do a triple screen test in (2nd trimester) looking for AFP, hCG, or estriol. |
| Describe Edwards syndrome | Extra autosome 18 usually b/c of the egg, limited chance of survival, 95% miscarry, maternal age effect. |
| Phenotypic characteristics of Trisomy 18 | low birth weight, severe mental retardation, small mouth, , low ears, tiny jaw, short sternum, clenched hands, rocker bottom feet, heart defects |
| Describe Patau syndrome | Extra autosome 13, 95% miscarry, 95% die within the first 6 monthsextra chromosome is donated by the egg, translocations are common. |
| Describe the phentypic characteristics of Patau syndrome | Microencephaly, holoprosencephaly, severe mental retardation, facial clefts, small abnormally shaped eyes, ASD, polydactyly |
| Describe Turner's syndrome | monosomy X --> inherits one X chromosome, and no second sex chromosome, all are female because you need a Y chromosome to become Male. |
| Phenotypic characteristics of Turner's syndrome | cystic hygroma about the neck, prenatal lymph blockage --> webbed neck, puffy hands and feet, low set ears. Left sided heart disease, VSD, COARCTATION OF THE AORTA!!! |
| Adult phenotype of Turner's syndrome | Short stature, normal intellegence, webbed neck, broad chest and nipples, 4th metacarpal, COARCTATION OF THE AORTA!!!, milkmaid arms, streak ovaries, failure of femininzation, amenorrhea, menopause before menstration |
| Genotype of Turner's syndrome | Only 50% are complete 45,X, mosaicism is very common too. |
| Describe Kleinfelter's syndrome | caused by an extra X chromosome (50% b/c of mother, 50% b/c of father) 47, XXY, higher risk of male breast cancer b/c of hyperestrogenism |
| Phenotype of Kleinfelter's syndrome | taller than average, facial features, very slight mental retardation (if any), gynecomastia, smaller genitals (hypogonadism), learning disabilities, long arms and legs |
| How are imprinted genes expressed? | They are expressed differently from the maternal or paternal allels. |
| Describe Prader-Willi Syndrome | deletion on the father's chromosome 15, (POP), and the mother's chromosome is turned off. |
| Describe Angelman's syndrome | Deletion on mother's chromosome 15 (Mother's are angels), and the chromosome is turned off. |
| Describe the Prader-Willi phenotype | Obesity (lock the fridge), hypotonia, outbursts of extreme violence, IQ's of 60-70, down turned mouth, hypogonadism |
| Describe the Angelman's phenotype | "Happy Puppet" syndrome, because of specific ataxia. paroxysmal laughter, no speech, severe mental retardation |
| Fragile-X repeats and mode of inheritance | CGG repeats in the FMR1 gene and X-linked (anticipation is more likely to occur when the gene is passed from mother to son) |
| Huntington's repeats and mode of inheritance | CAG and autosomal dominant (anticipation is more likely to occur when the gene is passed from father to child) |
| Describe Anticipation vs. Amplification | Anticipation = expecting the onset of the disease earlier in subsequent generations because of increased trinucleotide repeats Amplification = The expansion of trinucleotide repeats in subsequent generations. Results in a worsening of the disease. |
| Fragile-X repeat numbers | <40 CGG = no fragile X >200 CGG = have fragile X between 40 and 200 will not show classical fragile X, but will expand in the offspring. |
| Fragile-X phenotype | IQ of 35-50, long face, big jaw, big ears, big balls (females have milder features) |
| How to detect Fragile-X? | Use PCR |
| Huntington's repeat numbers | <26 = asymptomatic 27-35 = not symptomatic, but may have a child with an allele in the mutant range 36-39 May or may not develop symptoms if HD in their lifetime >40 Huntington Disease >60 Will get Huntington's before age 21 |
Created by:
lowrange4wd