Gene Polymorphism Associated With Macroangiopathy in Type 2 Diabetes Patients
Gene Polymorphism Associated With Macroangiopathy in Type 2 Diabetes Patients
To explore the possible implications of HLA-DRB1*04 alleles in patients with type 2 DM and
 macroangiopathy
Previous studies examining the molecular etiology of diabetes mellitus in China and abroad
 have mainly focused on the relationship between HLA and type 1 diabetes mellitus (DM) (1-3).
 Due to the complexity of type 2 DM heredity, few researchers have studied the correlation
 between type 2 DM and HLA. In recent years, it has been suggested that the development of
 coronary heart disease (CHD) in diabetic individuals is not merely a complication of diabetic
 macroangiopathy. CHD and diabetic macroangiopathy share some genetic associations. Previous
 studies have demonstrated that certain HLA*DRB1*04 subtypes are associated with an increased
 risk of cardiovascular disease.

 Experimental methods: For genomic DNA extraction, 3-5ml venous blood samples were collected
 from all patients. Coagulation was prevented using EDTA.

 The procedure for PCR amplification was as follows: denaturing for 100s at 96°C, annealing
 for 60s at 63°C, 1 cycle; denaturing for 10s at 96°C, annealing for 60s at 63°C, 9 cycles;
 denaturing for 10 s at 96°C, annealing for 30 s at 59°C; extending for 30 s at 72°C, 20
 cycles; maintaining at 4°C. Analyzing PCR products stained by Ethidium Bromide on 2.5%
 agarose gel electrophoresis. Bands were observed using an ultraviolet light and a biological
 imaging system.

 Statistical method: The degree of agreement with Hardy-Weinberg equilibrium was determined
 using the χ2 test. A t-test was employed for comparison of CRP levels (M ± s) and a χ2 test
 was performed to compare allelic frequencies. The relative risk rate (RR) was calculated as
 (Number of patients with the gene×Number of people in control group without the gene) divided
 by (Number of people in control group with the gene×Number of the patients without the gene).
 PC was calculated using Fisher's method if χ2 > 3.84.
Inclusion Criteria:

 -  clinical CHD (such as angina pectoris, myocardial infarction) diagnosed by dynamic
 electrocardiogram and ultrasonic cardiogram;

 -  coronary atherosclerosis confirmed by coronary angiographic examination;

 -  cerebral infarction diagnosed by cerebral CT;

 -  common carotid artery intimal-media thickness (IMT) ≥1.2 mm measured by Doppler
 ultrasonic examination;

 -  extensive irregular stenosis of a lower extremity artery (diameter < 3mm) or
 segmentally obstructed.

 Exclusion Criteria:

 -  age < 20 years

 -  age > 60 years