Single nucleotide polymorphisms in ABCG5 and ABCG8 genes in Chilean subjects with polygenic hypercholesterolemia and controls.
BACKGROUND
The excretion of cholesterol from liver and intestine is regulated by ATP-binding cassette half-transporters ABCG5 and ABCG8. Polymorphisms in their genes have been related to higher levels of plasma lipids. Thus, the aim of the present study was to evaluate the possible association between the 1950C > G (ABCG5) and the 251A > G (ABCG8) polymorphisms and the presence of hypercholesterolemia (HC) in Chilean subjects.


METHODS
A total of 118 non-related individuals with HC (total cholesterol, TC > or = 6.2 mmol/L) and 104 normolipidemic subjects (controls, TC < or = 5.17 mmol/L), aged 18 to 65 years old, were included in this study. The ABCG5 1950C>G and ABCG8 251A>G genotypes were assessed by polymerase chain reaction-restriction fragment length polymorphism.


RESULTS
The genotype distribution of the ABCG5/ABCG8 polymorphisms was in Hardy-Weinberg equilibrium in both groups. The frequency of CC homozygous genotype for ABCG5 1950C > G polymorphism was higher in HC patients than in controls (42% vs. 10%, p < 0.001). On the other hand, no significant differences for the 251A > G polymorphism of the ABCG8 gene were observed (p=NS). Nevertheless, HC subjects carrying the GG genotype for the 251A > G variant exhibited higher values of high-density lipoprotein cholesterol when compared to other genotypes (p=0.020).


CONCLUSIONS
Our data showed that the ABCG5 1950C > G polymorphism is associated with HC in the studied population. Nevertheless, this study is limited by its sample size.
Caamaño
José M
JM
Laboratorio de Biología Molecular y Farmacogenética, Departamento de Ciencias Básicas, Facultad de Medicina, Universidad de La Frontera, Temuco, Chile.
Pacheco
Alejandro
A
Lanas
Fernando
F
Salazar
Luis A
LA
D000071018:ATP Binding Cassette Transporter, Subfamily G, Member 5; D000071019:ATP Binding Cassette Transporter, Subfamily G, Member 8; D018528:ATP-Binding Cassette Transporters / Q000235:genetics*; D000293:Adolescent; D000328:Adult; D000368:Aged; D002677:Chile; D002784:Cholesterol / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D006937:Hypercholesterolemia / Q000097:blood / Q000235:genetics*; D008074:Lipoproteins / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D020412:Multifactorial Inheritance / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D014280:Triglycerides / Q000097:blood; D055815:Young Adult
C416945:ABCG5 protein, human; C416946:ABCG8 protein, human; D000071018:ATP Binding Cassette Transporter, Subfamily G, Member 5; D000071019:ATP Binding Cassette Transporter, Subfamily G, Member 8; D018528:ATP-Binding Cassette Transporters; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D008074:Lipoproteins; D014280:Triglycerides; D002784:Cholesterol