Associatioin between Taq 1B cholesterol ester transfer protein polymorphism and low HDL cholesterol concentrations in Saudis

Plasma concentrations of HDL (high-density lipoprotein) cholesterol are low in the Saudi Arabian population. A B polymorphism at the CETP (cholesteryl ester protein transfer) locus that is detectable with the restriction enzyme TaqI is agenetic determinant of the plasma HDL cholesterol concentration. We assessed the relationship between the TaqI B CETP polymorphism and lipid and apolipoprotein concentrations in a study sample of 335 Saudi residents. The TaqI B I and 132 allele frequencies were 0.54 and 0.46 respectively, similar to those in other populations. HDL cholesterol levels in 132132 homozygotes were significantly higher than in B I B I homozygotes [1.01 (0.3) compared with 0.92 (0.2) mmol/l; mean (S.D.); P=0.03]. There was also a significant difference between the 132132 and B I B I homozygotes with regard to apolipoprotein AI concentration [123.6 (16.4) compared with 113.7 (13.9) mg/dl; P = 0.04]. This genetic variation was independent of metabolic risk factors known to influence HDL cholesterol levels. The allele frequency of the TaqI B CETP polymorphism and its relatively modest impact on HDL cholesterol concentrations argue against an important role for this allele, or for strongly linked loci, in determining the low levels of HDL cholesterol seen in the Saudi population.