Galactokinase Deficiency (GALK1)
Galactokinase deficiency is an autosomal recessive disorder caused by pathogenic variants in the gene GALK1. While it has been diagnosed in individuals worldwide, there is an increased prevalence in the European Roma population. Patients with this disorder cannot break down the sugar in lactose, which accumulates in the eyes and is broken down to a metabolite that causes cataracts during the first months of life. Cataract formation can be prevented with dietary management. Rarely, patients with intellectual disability have been reported. Life expectancy is not reduced. No genotype-phenotype correlation has been reported, and therefore severity of the disease cannot be predicted.
For information about carrier frequency and residual risk, please see the residual risk table.