Arakawa's syndrome II

Arakawa's syndrome II
Other names	Methionine synthase deficiency, Tetrahydrofolate-methyltransferase deficiency syndrome, and N5-methylhomocysteine transferase deficiency.[1]
methylcobalamin
Named after	Tsuneo Arakawa

Arakawa's syndrome II^[2] is an autosomal dominant metabolic disorder that causes a deficiency of the enzyme tetrahydrofolate-methyltransferase; affected individuals cannot properly metabolize methylcobalamin, a type of Vitamin B₁₂.

Presentation

This disorder causes neurological problems, including intellectual disability, brain atrophy and ventricular dilation, myoclonus, hypotonia, and epilepsy.^{[citation needed]}

It is also associated with growth retardation, megaloblastic anemia, pectus excavatum, scoliosis, vomiting, diarrhea, and hepatosplenomegaly.^{[citation needed]}

Genetics

Arakawa's syndrome II is inherited in an autosomal dominant manner. This means the defective gene responsible for disorder is located on an autosome, and one copy of the defective gene is sufficient to cause the disorder when inherited from a parent who has the disorder.^{[citation needed]}

Diagnosis

Management

Eponym

It is called "Arakawa syndrome 2" after Tsuneo Arakawa (1949–2003), a Japanese Physician.;^[2][3] in this context, "Arakawa syndrome 1" refers to Glutamate formiminotransferase deficiency.

References

External links

• Arakawa's syndrome 2 at NIH's Office of Rare Diseases