Homocystinuria in a Family with Novel Cystathionine Beta Synthase Gene Mutations.

Background Classic homocystinuria is caused by cystathionine beta synthase deficiency owing to genetic mutations. The most common symptoms are ectopia lentis, osteoporosis, thrombosis, and mental retardation. This disease is prone to misdiagnosis and delayed diagnosis. Methods Here, we report a 19-year-old woman with Marfan's morphotype, high blood homocysteine, and a history of ectopia lentis. Total homocysteine levels became normal following treatment with vitamin therapy. Results Genetic analysis revealed two heterozygous nucleotide mutations in the parents. The mutation from the patient's father had not been described previously. Conclusions Screening for blood homocysteine should be performed early. Early diagnosis and treatment can prevent related symptoms.