Determination of the apolipoprotein E genotype using PCR-RFLP in kidney diseases.

Using polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP), genotypes of the apolipoprotein E (Apo E) were determined in 50 control subjects and 60 Thai kidney diseases patients including nephritic syndrome and chronic renal failure (CRF) (30 each). Exon 4 of the Apo E genomic DNA was amplified between nucleotide numbers 2849 and 3071 (270 base pairs) then digested with HhaI. It is observed that E3/3 was the most common genotype found in the control subjects (80%). In nephritic syndrome patients, E4/3 was found to be the most frequent (53.3%). On the contrary, E3/3 was found to be the most prominent in CRF patients (80%). There was a significant different of the Apo E genotype in hephrotic syndrome from the normal control subjects (p < 0.05 by X2 analysis). One the other hand, there was no significant difference of the Apo E genotype in CRF patients from the control subjects (p>0.5). Cholesterol and triglyceride levels of the E4/3 nephrotic syndrome patients were significantly different from the normal controls of the same genotype (p<0.05). Similarly, in CRF patients, triglyceride level of the E3/3 genotype was also significantly different from the normal controls of the same genotype (p<0.05). These results suggested that polymorphism of the Apo E genotypes may be associated with the lipid abnormalities in renal diseases.