Biochemistry - Genetic Diseases

Front 1

Mode of inheritance and major features: APKD

Back 1

AD; always bilateral; mutation in APKD1 (Chr 16); berry aneurysms, mitral valve prolapse (juvie form is recessive)

Front 2

Mode of inheritance and major features: familial hypercholesterolemia

Back 2

AD; elevated LDL from a defective or absent LDL receptor; severe atherosclerosis disease at young age; tendon xanthomas (achilles); may have MI before age 20

Front 3

Mode of inheritance and major features: Marfan's Syndrome

Back 3

AD; fibrilin gene mutation = connective tissue disorders; tall; aortic incomptenece and dissecting aortic aneurysms; floppy mitral valve

Front 4

Mode of inheritance and major features: Neurofibromatosis, type 1

Back 4

AD long arm of chr. 17; café-au-lait spots; neural tumors; Lisch nodules (pigmented iris hamartomas); pheo's

Front 5

Mode of inheritance and major features: Neurofibromatosis, type 2

Back 5

AD; bilateral acoustic neuroma, juvenile cataracts; NF2 gene on chr 22 (type 2 = 22)

Front 6

Mode of inheritance and major features: tuberous sclerosis

Back 6

AD; facial lesions (adenoma sebaceum); hypopigmented "ash leaf spots" on skin; cardiac rhabdomyomas; incomplete penetrance/variable presentation

Front 7

Mode of inheritance and major features: von Hippel-Lindau dz (VHL)

Back 7

AD; hemangioblastomas of the retina/cerebellum/medulla; 50% develop multiple bilateral renal cell carcinomas; deletion of VHL gene on Chr 3 (three words for Chr 3)

Front 8

Mode of inheritance and major features: Huntington's

Back 8

AD; triplet repeat disorder on chr 4; depression; progressive dementia; choreiform movements; caudate atrophy; decreased levels of GABA and ACh in brain

Front 9

Mode of inheritance and major features: Familial adenomatus polyposis

Back 9

AD; progresses to colon cancer unless resected; Deletion on chr. 5 (5 letters in polyp)

Front 10

Mode of inheritance and major features: Hereditary spherocytosis

Back 10

AD; spheroid erythrocytes; hemolytic anemia; increases MCHC; splenectomy is curative

Front 11

Mode of inheritance and major features: Achondroplasia

Back 11

AD; cell-signalling defect of fibroblast growth factor (FGF) receptor 3; dwarfism (short limbs but head and truck are normal size); associated with advanced PATERNAL age

Front 12

What gene is defective in cystic fibrosis?

Back 12

CFTR on chromosome 7

Front 13

What are the typical manifestations of a pt with CF?

Back 13

recurrent pulmonary infections (Pseudomonas and S. aureus); chronic bronchitis, bronchiectasis, pancreatic insufficency, meconium ileus in newborns infertility in males (absent vas deferens); fat soluble vitamin deficiencies

Front 14

What is the treatment for CF?

Back 14

n-acetylcysteine to loosen mucous plugs

Front 15

What is the pathophys of CF?

Back 15

defective Cl- channel --> secretion of abnormally thick mucus that plugs lungs, pancreas and liver

Front 16

What are some X-linked recessive disorders?

Back 16

Bruton's agammaglobulinemia, Fragile X, G6PD deficiency, ocular albinism, Lesch-Nyhan, Duchenne's, Hemophilia A and B, Fabry's dz, Hunter's syndrome

Front 17

Duchenne's MD is caused by what type of genetic mutation?

Back 17

Frame shift leading to deletion of the dystrophin gene

Front 18

What movement is a diagnostic sign of Duchenne's MD?

Back 18

Gower's maneuver

Front 19

What is age of onset Duchenne's MD?

Back 19

Before 5 years of age

Front 20

What are symptoms of Duchenne's MD?

Back 20

weakness begins in pelvic girdle muscles and progress superiorly, pseudohypertrophy of calf muscle, cardiac myopathy

Front 21

How are MD's diagnosed?

Back 21

increased CPK and muscle biopsy

Front 22

What is the less severe form of duchenne's MD?

Back 22

Becker's

Front 23

What is the 2nd most common cause of genetic mental retardation after Down's?

Back 23

Fragile X syndrome

Front 24

What are the clinical features of Fragile X syndrome?

Back 24

macro-orchidism, long face with a large jaw; large everted ears; autism

Front 25

What is the inheritance of Fragile X and pathophys?

Back 25

X-linked defect affecting the methylation and expression of the FMR1 gene

Front 26

What type of disorder is Fragile X?

Back 26

Triple repeat (CGG) - may show anticipation

Front 27

What are the trinucleotide repeat diseass?

Back 27

Huntington's, myotonic dystrophy, Friedreich's ataxia, Fragile X

Front 28

What are the three autosomal trisomies and which chr's are affected?

Back 28

Down's (21); Edward's (18); Patau (13)

Front 29

What are the prenatal signs of Down's?

Back 29

decreased a-fetoprotein, increased b-hCG, increased nuchal translucency

Front 30

Pts with Down's are at risk of developing what neurological disorder?

Back 30

early-onset Alzheimer's

Front 31

95% of Down's cases are due to what problem in meiosis? What is the associated parental "problem"?

Back 31

meiotic nondisjunction of homologous chromosomes; associated with advanced maternal age

Front 32

What are typical finding in Down's?

Back 32

mental retardation, flat facial profile, prominent epicanthal folds, simian crease, duodenal atresia, congenital heart disease, ASD

Front 33

What are the typical finding in Edwards?

Back 33

severe mental retardation, rocker bottom feet, low set ears, micrognathia, congenital heart disease clenched hand, prominent acciput

Front 34

What is the typical age of death in Edwards?

Back 34

within 1 year

Front 35

What are the typical findings in Patau's?

Back 35

severe mental retardation, microphthalmia, microcephaly, cleft lip/palate, abnormal forebrain structures, polyactyly, congential heart disease

Front 36

What is the typical age of death in Patau's?

Back 36

within 1 year

Front 37

Cri-du-chat is associated with what chromosomal abnormality?

Back 37

congenital deletion of short arm of chr 5

Front 38

What are the typical findings in Cri-du-chat?

Back 38

microcephaly, severe mental retardation, high-pitched crying/mewing, epicanthal folds, cardiac abnormalities

Front 39

22q11 syndromes are associted with what signs/symptoms?

Back 39

cleft papate, abnormal facies, thymic aplasia (t-cell deficiency), cardiac defects, hypocalcemia 2' to parathyroid aplasia;

Front 40

22q11 syndromes have variable presentation as what syndromes?

Back 40

DiGeorge syndrome (thymic, parathyroid, and cardiac defects) or velocardiofacial syndrome (palate, facial, cardiac defects)

Front 41

When are the risks for fetal alcohol syndrome the greatest?

Back 41

3-8 weeks

Front 42

What is the #1 cause of congenital malformations in the US?

Back 42

Fetal Alcohol Syndrome

Front 43

What are symptoms of Fetal alcohol syndrome?

Back 43

increased incidence of congenital abnormalities, pre and postnatal developmental retardation, microcephaly, facial abnormalities, limb dislocation and heart and lung fistulas