Biomarkers and diagnosis of congenital disorders of glycosylation

Abstract

Although valid and comprehensive diagnostic tests for CDG type I exist, there are limitations in the diagnosis of CDG type II, and many undiagnosed CDG type IIs must be expected. The apparent limitations of the methods used at present imply a necessity for new and broad diagnostic tools that comprise modern methodology to meet the requirements for screening tools.

International clinical guidelines for the management of phosphomannomutase 2‐congenital disorders of glycosylation: Diagnosis, treatment and follow up

“…Removal of sialic acid residues will unmask rare transferrin variants. Analysis of parental transferrin can also rule out the presence of hereditary variants . Noteworthy, PMM2‐CDG newborns and infants might present a normal profile that later on becomes abnormal.…”

“…Analysis of parental transferrin can also rule out the presence of hereditary variants. 136 Noteworthy, PMM2-CDG newborns and infants might present a normal profile that later on becomes abnormal. Conversely, the transferrin pattern sometimes normalizes with age, without improvement of the symptoms, as reported in one patient.…”

Landmark Evaluation of Transferrin Glycoforms: Pioneering Congenital Glycosylation Disorder Diagnosis in Cuba

“…Therefore, the experimental use of IEF for the evaluation of serum Tf glycoforms in the present study is justified. To validate the technique and its interpretation, the standardized isoelectric patterns given by Pérez-Cerdá et al in 2006 [40], de Jong and van Eijk in 1988 [55], Lefeber et al in 2011 [84], and Denecke in 2009 [85] with controls confirmed by HPLC-MS. The bands, characteristic of each Tf glycoform, corresponded to international standards; hence, the validation of the IEF method for serum Tf on manually prepared gels was assumed.…”

“…There was a correlation between the isoform patterns of serum Tf using the standardized method in the scientific literature [40,55,84,85] and the controls analyzed on the model 111 Mini IEF Cell equipment (Figure 1). Solution A was prepared by mixing 1 g of copper sulphate (CuSO4) and 100 ml of acetic acid, and then making up to 500 ml with distilled water.…”