Common polymorphisms in interleukin genes (IL4, IL6, IL8 and IL12) are not associated with alcoholic liver disease or alcoholism in Spanish men.
BACKGROUND
Preliminary data suggest that polymorphisms in cytokine genes may be involved in the genetic predisposition to alcoholic liver cirrhosis or alcohol use disorders. We thus analyze the association between these diseases and the following polymorphisms: -33T>C IL4, -174 G>C IL6, -251 T>A IL8 and 1188 A>C IL12B.


METHODS
258 male alcoholics (161 without liver disease and 97 with liver cirrhosis) and 101 healthy controls were genotyped for the above mentioned polymorphisms. We examined the relationship between genotype and allele frequencies and the presence of disease, as well as the correlation with combinations of putative pro-inflammatory genotypes. Haplotypes were inferred using the expectation-maximization algorithm and haplotype frequencies were compared.


RESULTS
We found no statistically significant association between any of these polymorphisms or the combinations of pro-inflammatory polymorphisms and the risk of alcoholic liver cirrhosis or alcohol abuse or dependence. Haplotype analysis of the IL4 and IL12B polymorphisms did not show any statistical relationship either.


CONCLUSIONS
Our results do not support the hypothesis that the analyzed polymorphisms confer differences in alcoholic liver cirrhosis or alcohol use disorders susceptibility.
Marcos
Miguel
M
Unidad de Alcoholismo, Servicio de Medicina Interna II, Hospital Universitario de Salamanca, Paseo de San Vicente 58-182, 37007, Salamanca, Spain. migmarmar10@hotmail.com
Pastor
Isabel
I
González-Sarmiento
Rogelio
R
Laso
Francisco-Javier
FJ
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000437:Alcoholism / Q000235:genetics*; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006801:Humans; D018664:Interleukin-12 / Q000235:genetics*; D015847:Interleukin-4 / Q000235:genetics*; D015850:Interleukin-6 / Q000235:genetics*; D016209:Interleukin-8 / Q000235:genetics*; D008104:Liver Cirrhosis, Alcoholic / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic
D015850:Interleukin-6; D016209:Interleukin-8; D018664:Interleukin-12; D015847:Interleukin-4