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Letters |

Retinopathy in Inherited Transcobalamin II Deficiency

Aruna Dharmasena, MBBS; Antonio Calcagni, MD; Andrea R. Kerr, FRCS(Ed)
Arch Ophthalmol. 2008;126(1):141-142. doi:10.1001/archophthalmol.2007.21.
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Transcobalamin II (TCII) is a primary plasma protein that binds vitamin B12 and facilitates its cellular uptake by many tissues.1 Inherited deficiency of TCII is a rare autosomal recessive disorder that results in severe megaloblastic anemia in early infancy despite normal serum vitamin B12 levels.

Rosenblatt  DSWhitehead  VM Cobalamin and folate deficiency: acquired and hereditary disorders in children. Semin Hematol 1999;36 (1) 19- 34
Souied  EHBenhamou  NSterkers  M  et al.  Retinal degeneration associated with congenital transcobalamin II deficiency. Arch Ophthalmol 2001;119 (7) 1076- 1077
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Composite of the retinal appearance of the right and left eyes at age 48 years showing bilateral maculopathy and significant pigmentary changes nasal to the optic disc.

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