Sialic acid-deficient serum and cerebrospinal fluid transferrin in a newly recognized genetic syndrome

Identical twin-sisters with evidence of a demyelinating disease showed multiple serum glycoprotein abnormalities. The association of a low serum iron level and a normal blood haemoglobin suggested an abnormality of transferrin too. This was confirmed by finding a sialic acid-deficiency of this glycoprotein in serum as well as in cerebrospinal fluid.