Since 1967 a syndrome characterized by renal disease, normochromic anaemia and corneal opacities has been described in 7 members of 3 different Norweigan families. The patients have low levels of esterified cholesterol and lack LCAT (lecithin: cholesterol acyltransferase) activity in plasma. The genetic basis of the disorder seems to be the presence of a LCAT deficiency gene in double dose. This gene is probably the result of a single mutational event. Linkage studies revealed non-random assortment between LCTA deficiency and serum haptoglobin (Hp) types. After Hp subtyping a combined lod score of 3-41 at a recombination fraction of 0-00 was obtained. Association was revealed between the LCAT deficiency gene and the Hp-1S gene. We propose that the LCAT gene is situated close to the alpha-haptoglobin locus on chromosome no. 16.