Association Study Between VDR Gene Polymorphisms and Risk and Features of MG in Han Chinese Population

Beijing Tongren Hospital297 enrolled

Overview

The Vitamin D receptor gene (VDR) polymorphisms are the candidate genetic variants for susceptibility to autoimmune diseases. In the present study, the investigators aimed to assess the association between VDR polymorphisms and myasthenia gravis (MG) susceptibility and disease features in Chinese Han population.The patients with MG and healthy controls were genotyped for VDR rs1544410, rs2228570, rs731236, and rs7975232 polymorphisms using the improved multiple ligase detection reaction. Information on age at onset, acetylcholine receptor antibody (AChR-Ab) and muscle-specific kinase antibody (MuSK-Ab) status, thymus status, involved muscles at onset and Osserman type at the maximum worsening during 2 years follow-up were obtained and used as the grouping basis of sub-classifications. Intergroup comparisons of allele and genotype frequencies, haplotype distributions were performed between MG group and the control group, and between each pair of MG subgroups.

Study Type

OBSERVATIONAL

Enrollment

297

Conditions

Myasthenia Gravis, Ocular Gene Polymorphism

Interventions

Genotype analysis for VDR rs1544410, rs2228570, rs731236, and rs7975232 polymorphisms

Genomic DNA was extracted from peripheral blood samples using a Wizard Genomic DNA Purification Kit (Promega, Madison,Wisconsin, USA) as per the product instruction. VDR (rs731236, rs1544410, rs7975232, rs2228570) polymorphisms were genotyped by the improved Multiple Ligase Detection Reaction (iMLDR) developed by Genesky Biotechnologies Inc. (Shanghai, China).

Eligibility

Sex: ALLMin age: 16 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * Clinical diagnosis of myasthenia gravis. * Han Chinese population. * Must be able to complete a 2-year follow-up visit. Exclusion Criteria: * Clinical data collection can not be completed. * Poor compliance.

Outcomes

Primary Outcomes

Association between VDR gene polymorphism and MG susceptibility

Codominant, dominant and recessive genetic models and haplotype analysis were applied to compare the difference between MG and control groups.

Time frame: up to 2 years

Secondary Outcomes

Association of VDR gene polymorphism with MG subgroups

To study the precise effect of single nucleotide polymorphisms (SNPs) in the different population, the MG patients were divided into subgroups according to essential clinical variables, including onset age (≤50 or \>50 years), thymus status (thymoma or non-thymoma, by pathology), AChR / MuSK Abs (positive or negative), onset involvement (ocular or generalized) and Osserman type at the maximum worsening (type I or IIa-IIb or III-V). The investigators analyzed the distribution of genes in each group.