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USMLE Step 1 - Biochem

DiseaseDeficient enzyme, Findings
Hurler's syndrome (autosomal recessive) alpha-L-iduronidase; developmental delay (mental retardation), gargoylism, airway obstruction, corneal clouding, hepatosplenomegaly, MI, dwarfing, increase in heparan & dermatan sulfate
Scheie Syndrome (autosomal recessive) alpha-L-iduronidase (different mutation from Hurler's); mildest form of mucopolysaccharidosis Type 1, causes corneal clouding, nml intelligence, aortic valve disease, stiff joints, also accumulation of heparan & dermatan sulfate (different ratios)
Hunter's syndrome (X-linked recessive) iduronate sulfatase; mild Hurler's + aggressive behavior, no corneal clouding, mental retardation & various physical deformities, accumulation of heparan & dermatan sulfate (different ratios)
Created by: jerrica_08