Polymorphisms in the interleukin-6 receptor gene (Asp358Ala) and body mass index in Chilean women with type 1 diabetes.
BACKGROUND
Interleukin-6 receptor (IL6R) has been linked with type 2 diabetes and obesity. The presence of the Asp allele in Asp358Ala of IL6R has been linked with insulin resistance and weight gain.


OBJECTIVE
The aim of this study is to evaluate the frequency and the association of the Asp358Ala in the IL6R gene in Chilean women with type 1 diabetes (T1D) and its relationship with body mass index (BMI).


METHODS
One hundred and forty-five patients with T1D (N = 145) and healthy control women (N = 103) were recruited. The polymorphisms were studied with polymerase chain reaction and restriction fragment length polymorphisms. The effect of the polymorphisms on BMI and age of diagnosis was evaluated.


RESULTS
A higher frequency of the Asp allele was observed in patients with T1D compared with controls (0.483 vs. 0.364; p < 0.01). The Asp358Asp genotype was more prevalent in the T1D group compared with controls (0.152 vs. 0.097; p < 0.01). T1D patients younger than 19 years had a positive association of BMI-standard deviation scores with the Asp allele (p < 0.05). Finally, lower Glycated Hemoglobin 1c (HbA1c) levels were observed in patients carrying the Asp allele (p < 0.01).


CONCLUSIONS
T1D in Chilean women appears to be associated with the presence of the Asp allele in IL6R. The IL6R polymorphism (Asp358/Asp) was associated with BMI in T1D patients. This genetic variant could have some role in weight gain in T1D women.
Laboratory of Nutritional Genomics, Department of Nutrition, University of Chile, Santiago, Chile. fperez@med.uchile.cl
Francisco
F
Pérez-Bravo
Ana María
AM
Oyarzún
Francisca
F
Soto
Patricia
P
López
Francisca
F
Eyzaguirre
Ethel
E
Codner
D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D015992:Body Mass Index; D002648:Child; D002677:Chile / Q000453:epidemiology; D003922:Diabetes Mellitus, Type 1 / Q000453:epidemiology / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D056726:Genetic Association Studies; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D011110:Polymorphism, Genetic; D020641:Polymorphism, Single Nucleotide; D015995:Prevalence; D019947:Receptors, Interleukin-6 / Q000235:genetics*; D015430:Weight Gain / Q000235:genetics; D055815:Young Adult
D006442:Glycated Hemoglobin; D019947:Receptors, Interleukin-6; C508603:IL6R protein, human; C517652:hemoglobin A1c protein, human