Our study was carried out at a family from the Sahel (Tunisia). The father (index case) and his two children (son and daughter). The father beta-glucocerebrosidase (GCB) activity showing a deficit. These biochemical analyses are supplemented by molecular studies: enzymatic digestion and the direct sequencing. Two mutations were analysed, the p.Asn 370 Ser and the p.Leu 444 Pro. The DNA sequencing confirmed the presence of the homozygous genotype of this p.Asn 370 Ser in the father DNA and the heterozygous one in the two children DNA. It has no detection of the 55 pb deletion in exon 9 among all the specimens of DNA treated. The mutation p.Asn 370 Ser is associated with Gaucher disease type 1 correlated of a total absence of neurological involvements.