Evidence of gene dosage effect for HK 1 in the red cells of a patient with trisomy 10pter leads to p13.

Quantitative evaluation of six red cell enzymes in a patient with trisomy 10p syndrome showed significantly increased activity levels of HK 1. These results are in agreement with the evidence derived from another similar patient and strongly support the idea of gene dosage effect of HK1 in the erythrocytes of 10p trisomics. It is suggested that the HK 1 structural locus may be in the 10 pter leads to p13 region.