- lacks a-galactosidase A

- accumulates Ceramide trihexoside

- Peripheral neuropathy, Renal Dz, angiokeratomas

- X-linked recessive

Fabry's Dz

- lacks Glucocerebrosidase

- accumulates Glucocerebroside

- Autosomal recessive

- Hepatosplenomegaly (HSM), aseptic necrosis of femur, crumpled tissue paper macrophages

- Most common

- Ashkenazi Jews

Gaucher's Dz

- lack sphingomyelinase

- accumulate sphingomyelin

- Progessive neurodegeneration, HSM, cherry-red spot on macula, foam cells

- Autosomal recessive

- Ashkenazi Jews

Niemann-Pick Dz

- lack Hexoaminidase A

- accumulate GM₂ ganglioside

- progressive neurdegeneration, developmental delay, cherry-red spot on macula, lysosomes w/ onion skin

- Autosomal recessive

- Ashkenazi jews

Tay-Sachs Dz

- lack a-galactocerebrosidase

- accumulate galactocerebroside

- peripheral neuropathy, developmental delay, optic atrophy, globoid cells

- autosomal recessive

- death by 3 y/o

Krabbe's Dz

- lack arylsulfatase A

- accumulate cerebroside sulfate

- demyelination with ataxia, dementia

- autosomal recessive

Metachromatic leukodystrophy

- lack a-L-iduronidase

- accumulate heparan/dermatan sulfate

- developmental delay, gargoylism, corneal clouding, HSM

- autosomal recessive

- mild form is Scheie's syndrome

Hurler's syndrome

-lack iduronate sulfate

- accumulate heparan/dermatan sulfate

- aggressive behavior, no corneal clouding, gargoylism, developmental delay, HSM

- X-linked recessive

Hunter's syndrome

- lack mannose-6-phosphorylation

- no lysosomal marking

- products released into system --> death by 6 y/o

I-cell Dz