Apolipoprotein A polymorphisms and plasma lipoprotein(a) concentrations in non-Hispanic Whites and Hispanics.
Elevated levels of plasma lipoprotein(a) [Lp(a)] are thought to be a risk factor for atherosclerosis and coronary heart disease. Plasma levels of Lp(a) are highly variable between individuals, ranging from 0.1 mg/dL to > 100 mg/dL These levels are under strict genetic control, and genetic variation in the apolipoprotein A (APOA) gene accounts for almost all variation in Lp(a) levels. In this study, we investigated the relationship between two APOA polymorphisms (kringle 4 and 5' pentanucleotide repeat) and plasma Lp(a) levels in normoglycemic non-Hispanic Whites (NHWs) (n = 390) and Hispanics (n = 214) from the San Luis Valley, Colorado. Mean (+/- SD) and median Lp(a) levels were 9.6 +/- 12.5 mg/dL and 3.8 mg/dL, respectively, in NHWs and 12.1 +/- 15.6 mg/dL and 4.9 mg/dL, respectively, in Hispanics. The number of observed kringle 4 repeats ranged from 11 to 38 in NHWs and from 10 to 41 in Hispanics. Spearman rank correlation revealed an inverse relationship between the size of the kringle 4 repeat and plasma Lp(a) levels in both populations (r = -0.38; p < 0.0001 in NHWs and r = -0.64; p < 0.0001 in Hispanics). About 30% and 48% of the variation in plasma Lp(a) was explained by this polymorphism in NHWs and Hispanics, respectively. This study confirms that the kringle 4 polymorphism in the APOA gene is a significant determinant of Lp(a) levels in both study groups. A pentanucleotide repeat polymorphism in the 5' promoter region of the APOA gene did not show significant impact on plasma Lp(a) levels in either NHWs or Hispanics.
Chiu
L
L
Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, PA 15261, USA.
Hamman
R F
RF
Kamboh
M I
MI
D000704:Analysis of Variance; D001054:Apolipoproteins A / Q000235:genetics*; D002318:Cardiovascular Diseases / Q000235:genetics; D003120:Colorado; D014644:Genetic Variation / Q000235:genetics*; D005838:Genotype; D006630:Hispanic or Latino / Q000235:genetics*; D006801:Humans; D018082:Kringles / Q000235:genetics; D017270:Lipoprotein(a) / Q000097:blood* / Q000235:genetics*; D018895:Microsatellite Repeats / Q000235:genetics*; D011110:Polymorphism, Genetic / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics; D018709:Statistics, Nonparametric; D044465:White People / Q000235:genetics*
D001054:Apolipoproteins A; D017270:Lipoprotein(a)