Premium
Association between Pro12Ala polymorphism of the PPAR‐γ2 gene and insulin sensitivity in Brazilian patients with type‐2 diabetes mellitus
Author(s) -
Tavares V.,
Hirata R. D. C.,
Rodrigues A. C.,
Monte O.,
Salles J. E. N.,
Scalissi N.,
Speranza A. C.,
Hirata M. H.
Publication year - 2005
Publication title -
diabetes, obesity and metabolism
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.445
H-Index - 128
eISSN - 1463-1326
pISSN - 1462-8902
DOI - 10.1111/j.1463-1326.2004.00453.x
Subject(s) - medicine , endocrinology , biology , type 2 diabetes mellitus , insulin , insulin resistance , restriction fragment length polymorphism , allele , glucose homeostasis , type 2 diabetes , diabetes mellitus , genetics , gene , genotype
Aim: Peroxisome‐proliferator‐activated receptor‐γ2 (PPAR‐γ2) is a nuclear receptor that plays an important role in lipid metabolism and insulin sensitivity. The purpose of this study is to investigate the association of Pro12Ala polymorphism at the PPAR‐γ2 gene in Brazilian patients with type‐2 diabetes mellitus (T2D m ) and controls (CG). Methods: Genomic DNA was obtained from 207 unrelated white people presenting with T2D m and from 170 controls. Anthropometric data included body mass index and waist to hip ratio. Biochemical parameters included fasting plasma glucose, total cholesterol, high‐ and low‐density lipoprotein cholesterol, triglycerides, glycated haemoglobin and insulin. Systolic and diastolic blood pressures were also measured. Screening for mutations in the entire coding region of the PPAR‐γ gene was performed by means of polymerase chain reaction (PCR), single‐strand conformational polymorphism and sequencing. Pro12Ala polymorphism was analysed by using PCR‐RFLP (restriction fragment‐length polymorphism). Results: One base substitution was identified – a C to G substitution in exon B of the PPAR‐γ2 gene. The frequency of the Ala12 allele in T2D m (0.09) was similar to that found in CG (0.06, p = 0.185). In the T2D m group, Ala12 allele was associated with lower fasting plasma insulin levels (p = 0.036) and higher insulin sensitivity (p = 0.049) by means of homeostasis model assessment. Among obese people, there was no association between any of the T2D m or obesity‐related traits and the Pro12Ala polymorphism. Conclusions: The results of our study suggest that people with the Ala12 allele of the PPAR‐γ2 gene could be more sensitive to insulin than those carriers of the Pro12 allele among Brazilian Caucasians.