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Old 08-06-2014
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Help Homocystinuria

Homocystinuria is an autosomal recessive disease caused by mutations in the CBS gene. It involves abnormalities in the enzyme cystathionine beta-synthase (CBS) that breaks down the amino acid homocysteine.
Symptoms of Homocystinuria:

Developmental delays/mental retardation
Ectopic lentis (dislocation of the lens of the eye)
Myopia (nearsightedness)
Skeletal abnormalities (excessive height and length of the limbs)
Risk for osteoporosis (low bone density) at an early age
Thromboembolism (blood clots)
Psychiatric problems

Symptoms are believed to be due to the toxic build-up of homocysteine and its metabolites in the body.

Could you please explain how does a toxic level of homocystane exactly cause those abnormalities related to Connective Tissue? (Marfanoid Habitus, lens dislocation, osteoporosis) ?
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Old 08-06-2014
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i believe due to the sh groups of cystiene which are electron donors(reduce thesmelves but oxidize other compounds) once the sh groups donate the electrons they cross link with sh groups in other proteins in connective tissue altering function. I THINK this is the mechanism
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