RecTL: a complex allele of the glucocerebrosidase gene associated with a mild clinical course of Gaucher disease.

We describe 4 Jewish patients with type 1 Gaucher disease and the genotype N370S/recTL. They present either asymptomatic or mild Gaucher disease. RecTL is a complex allele that contains 4 single point mutations in the glucocerebrosidase gene: D409H, L444P, A456P, and V460V. Since patients who have the genotype N370S/L444P usually develop a moderate to severe course of Gaucher disease, and those who are homozygous for the D409H or the L444P mutations develop aggressive disease accompanied by neurological signs, it is of great importance to distinguish between the severe single base pair mutations and the mild complex recTL allele. This distinction should prove useful in assessing the natural history of Gaucher disease and in considering the indications for early enzyme replacement therapy.