Module 7-8 Review Flashcards
What enzyme deficiency leads to Lesch-Nyhan syndrome
Hypoxanthine-guanine phosphoribosyltransferase (HGPRT)
What is a major symptom of Lesch-Nyhan syndrome
Self-mutilating behavior of lips and finger biting
What enzyme is inhibited by allopurinol
Xanthine oxidase
What disease is characterized by needle-shaped urate crystals in joints
Gout
How do urate crystals appear under polarizing light microscopy
Yellow when aligned parallel to the red compensator axis, blue when perpendicular
What crystal deposits cause pseudogout
Calcium pyrophosphate dihydrate
What enzyme defect causes orotic aciduria
Uridine-5-phosphate synthase
What are the symptoms of orotic aciduria
Growth retardation, anemia, increased orotic acid in urine
What drug is a ribonucleotide reductase inhibitor used to treat sickle cell anemia
Hydroxyurea
What is the inheritance pattern of X-linked sideroblastic anemia
X-linked recessive
What is a key feature of X-linked sideroblastic anemia
Microcytic and hypochromic anemia
What molecule is synthesized in erythrocytes and hepatocytes
Heme
What form of iron can bind oxygen
Ferrous (Fe2+)
What type of hemoglobin has the highest oxygen affinity
Fetal hemoglobin (HbF)
Which enzyme deficiency causes methemoglobinemia
NADH-Cytochrome b5 reductase
Where does erythropoiesis occur after birth
Bone marrow
What mutation is associated with polycythemia vera
JAK2 gain-of-function mutation
What is the effect of 2,3-BPG on hemoglobin
Reduces oxygen binding affinity
What vitamin deficiency is associated with neural tube defects
Folic acid (Vitamin B9)
What condition is caused by a defect in UDP-glucuronosyltransferase (UGT1A1)
Crigler-Najjar syndrome
What is the major storage form of iron in the body
Ferritin
What gene is mutated in Hereditary Hemochromatosis Type 1
HFE gene
What is a clinical feature of Hereditary Hemochromatosis Type 2
Severe iron overload at an early age
What type of hemoglobin predominates in adults
Hemoglobin A (HbA)
What enzyme is deficient in Gaucher disease
Glucocerebrosidase
What is the inheritance pattern of Tay-Sachs disease
Autosomal recessive
What genetic mutation is associated with Lynch syndrome
DNA mismatch repair genes (MLH1, MSH2, EPCAM)
What type of DNA repair corrects small, non-helix-distorting base lesions
Base Excision Repair (BER)
What is the function of clathrin
Formation of coated vesicles
What is a symptom of Vitamin B12 deficiency
Pernicious anemia
What is the inheritance pattern of Fabry disease
X-linked recessive
What are the symptoms of Hunter syndrome
Mild Hurler plus aggressive behavior
What gene is mutated in Li-Fraumeni syndrome
TP53 gene (p53 protein)
What enzyme is missing in I-cell disease
N-Acetylglucosamine-1-phosphotransferase
What protein is absent in Duchenne Muscular Dystrophy (DMD)
Dystrophin