The Chicago variant of clinical galactosemia

✍ Scribed by Claramma M. Chacko; Rebecca S. Wappner; Ira K. Brandt; Henry L. Nadler

• Book ID: 104753729
• Publisher: Springer
• Year: 1977
• Tongue: English
• Weight: 538 KB
• Volume: 37
• Category: Article
• ISSN: 0340-6717
• DOI: 10.1007/bf00393607

✦ Synopsis

A new variant of clinical galactosemia with two hitherto unidentified alleles on the transferase locus in one family is described. This new clinical variant of transferase has 25% of normal control activity in blood and in skin fibroblasts, and the patient accumulates galactose-1-phosphate in blood on an unrestricted galactose diet. Using starch gel electrophoresis on the hemolysate of the family members, a fast-moving transferase with mobility in between those of the normal control and of the Duarte variant is identified. This new allele is designated as GALTC1 (fast-moving Chicago variant). In addition, a second new allele was documented in this family by studying the instability of the transferase enzyme in hemolysates of family members at 50 degrees C for various time intervals. This new allele is designated as GALTC2 (heat-labile Chicago variant). On the basis of these studies, the transferase genotype of this patient is thought to be a double heterozygote compound, GALTC1/GALTG.