Association of polymorphisms at restriction enzyme recognition sites of apolipoprotein B and E gene with dyslipidemia in children undergoing primary nephrotic syndrome.
BACKGROUND
Dyslipidemia, a common complication, is very prevalent in children with primary nephrotic syndrome (PNS). Recent studies have shown that genetic basis may be involved in the onset of HLP secondary to PNS. ApoB and E have been identified as the important candidate genes for lipid abnormalities.


OBJECTIVE
To investigate the association of apolipoprotein B (apoB) and E (apoE) genetic polymorphisms (Xba I, EcoR I, Msp I, and Hha I) with parameters describing the serum lipid profiles in children undergoing PNS.


METHODS
Genomic DNA was extracted from 250 children diagnosed with PNS and 200 healthy controls with neither allergic nor renal disease. ApoB (Xba I, EcoR I, and Msp I) and apoE (Hha I) genotypes were determined by PCR-restriction fragment length polymorphism (RFLP) analysis. The fasting serum lipoprotein (a) [Lp(a)], total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), apolipoprotein A1 (apoA1), apoB, and total protein from a 24-h urine sample were measured.


RESULTS
No significant differences in genotypes and alleles frequencies were observed for the apoB Xba I, EcoR I, Msp I and the apoE Hha I restriction sites in PNS patients as compared to controls (P > 0.05). Patients and controls with X + allele exhibited significantly higher serum levels of Lp(a), TC, nonHDL-C, LDL-C, LDL-C/HDL-C ratio, and apoB than that with X- allele (P < 0.05), whereas for apoA1/B ratio the opposite was found (P < 0.01). E-/E- carriers had significantly higher Lp(a), TC, HDL-C, and apoA1 concentrations than did E+/E- or E+/E+ carriers in control group (P < 0.05). Healthy children carrying the rare EcoR I allele had higher mean Lp(a), TC, and HDL-C levels than homozygotes for E+ (P < 0.05). Higher Lp(a) serum concentrations were observed in patients with E- allele (P < 0.05). No significant differences in lipid parameters were determined for the apoB Msp I and apoE Hha I the polymorphisms study (P > 0.05). When genetic variations were compared with urinary protein excretion, the Xba I X- allele was more frequent in patients with elevated proteinuria (P < 0.01).


CONCLUSIONS
Presence of Xba I X+ allele and/or EcoR I E- at the apoB gene may be risk factors for lipid abnormalities secondary to childhood PNS.
Department of Pediatrics, First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region, China.
Peng
P
Hu
Yuan Han
YH
Qin
Cheng Xue
CX
Jing
Feng Ying
FY
Lei
Ping
P
Chen
Ming Fang
MF
Li
D000293:Adolescent; D001055:Apolipoproteins B / Q000235:genetics*; D001057:Apolipoproteins E / Q000235:genetics*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D004262:DNA Restriction Enzymes / Q000378:metabolism*; D050171:Dyslipidemias / Q000097:blood / Q000150:complications* / Q000235:genetics; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006801:Humans; D008055:Lipids / Q000097:blood; D009404:Nephrotic Syndrome / Q000097:blood / Q000150:complications* / Q000235:genetics; D011110:Polymorphism, Genetic
D001055:Apolipoproteins B; D001057:Apolipoproteins E; D008055:Lipids; D004262:DNA Restriction Enzymes