Genetic counseling for Gaucher disease is complicated by the vast degree of clinical heterogeneity encountered in the disorder. Recent advances in our understanding of the molecular genetics of Gaucher disease are particularly relevant to genetic counseling. Although the identification of mutations in the glucocerebrosidase gene has enabled genotypic screening of Gaucher patients, the ability to reliably predict patient outcome on the basis of DNA studies is often limited. An appreciation of both the spectrum of clinical manifestations in Gaucher patients and the limitations of the available genotypic information is necessary when counseling patients, families and at-risk individuals.