The aim of this study has been to assess the clinical presentation and biochemical profile of lipoid proteinosis within a defined pedigree. Glycoprotein analysis was compared to normal values in an attempt to define a biochemical phenotype. Six affected family members were identified with variable degrees of disease expression. The most likely mode of inheritance is autosomal recessive due to consanguinity. Routine laboratory investigations were normal in all family members tested. The total content of mucopolysaccharides, sialic acid and hexosamine in biopsed tissue was significantly lower than normal. Our findings demonstrate that a defect in glycoprotein synthesis, possibly enzymatic, may be the cause of lipid proteinosis and its protean clinical manifestations.