Clinical Trial: Gene Polymorphism Associated With Macroangiopathy in Type 2 Diabetes Patients

Study Status: Completed
Recruit Status: Completed
Study Type: Observational

Official Title: Polymorphism Analysis of HLA-DRB1*04 Alleles in Patients With Type 2 Diabetic Macroangiopathy in Northeast Chinese

Brief Summary: To explore the possible implications of HLA-DRB1*04 alleles in patients with type 2 DM and macroangiopathy

Detailed Summary:

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 witho
Sponsor: First Affiliated Hospital of Harbin Medical University

Current Primary Outcome: Test of allelic frequencies [ Time Frame: At recruitment ]

A commercially available kit was used for extraction of genomic DNA from the whole blood samples (PEL-FREEZ Inc., USA). Thirty-two pairs of sequence-specific primers (SSP) for HLA-DRB1*04 alleles were purchased from One Lambda, Inc. (USA), and the Taq enzyme was purchased from Promega Corp. (USA). The PCR-SSP technique was employed to determine the HLA-DRB1*04 alleles for each subject. Genes were amplified using the 5700 PCR thermal cycler manufactured by Applied Biosystems Inc. (USA).


Original Primary Outcome: Same as current

Current Secondary Outcome: Evaluation of serum CRP(C-reactive protein) levels [ Time Frame: At recruitment ]

A commercially available 96-well plate ELISA assay kit (introassay CV 1.7%~3.9%, interassay CV 2.8%~5.1%) was used to quantify hs-CRP in serum (DSL Inc., USA). All samples were evaluated in duplicate. The absorbance (OD) was determined using a BIO-RAD2550 microwell plate reader (USA).


Original Secondary Outcome: Same as current

Information By: First Affiliated Hospital of Harbin Medical University

Dates:
Date Received: August 25, 2016
Date Started: May 2015
Date Completion:
Last Updated: August 25, 2016
Last Verified: August 2016