High C4 gene copy numbers protects against Vogt-Koyanagi-Harada syndrome in Chinese Han

Related Experiment Video

Updated: Apr 24, 2026

HOX Loci Focused CRISPR/sgRNA Library Screening Identifying Critical CTCF Boundaries
10:10

HOX Loci Focused CRISPR/sgRNA Library Screening Identifying Critical CTCF Boundaries

Published on: March 31, 2019

7.7K

Shengping Hou1, Jian Qi1, Dan Liao1

  • 1The First Affiliated Hospital of Chongqing Medical University, Chongqing, China Chongqing Key Laboratory of Ophthalmology, Chongqing, China Chongqing Eye Institute, Chongqing, China.

The British Journal of Ophthalmology
|September 4, 2014
PubMed

Insights

Vogt-Koyanagi-Harada (VKH) syndrome patients show lower serum C4 levels and fewer C4 gene copies. This suggests a link between complement C4 gene copy number variation and VKH disease risk.

Area of Science:

  • Immunogenetics
  • Autoimmune Diseases
  • Complement System

Background:

  • The complement system, particularly C4, plays a role in autoimmune diseases.
  • Copy number variation (CNV) in C4 genes is associated with immune responses.
  • Vogt-Koyanagi-Harada (VKH) syndrome is a rare autoimmune disorder affecting multiple organs.

Purpose of the Study:

  • To investigate the association between C4 copy number variation (CNV) and Vogt-Koyanagi-Harada (VKH) syndrome.
  • To determine if C4 gene dosage affects C4 expression levels in VKH patients.

Main Methods:

  • Real-time PCR was used to analyze C4 CNVs in 1027 VKH patients and 2083 controls.
  • Serum C4 levels were measured.
  • Peripheral blood mononuclear cells (PBMCs) were cultured to assess cytokine production (Th1 and Th17).

Main Results:

  • Serum C4 levels were significantly lower in VKH patients compared to controls.
  • A strong positive correlation was observed between C4 gene copy number and serum C4 expression.
  • VKH patients exhibited significantly lower frequencies of high C4A and total C4 gene copy numbers.
  • C4 association with VKH was independent of HLA-DR4.
  • No association was found between C4A copy number and Th1/Th17 cytokine production.

Conclusions:

  • Decreased serum C4 expression and a reduced frequency of high C4 gene copy number are characteristic of VKH syndrome.
  • These findings highlight the role of C4 gene dosage in the pathogenesis of VKH.
Abstract

Keywords:
ImmunologyInflammation

More Related Videos

Investigating the Pathogenesis of MYH7 Mutation Gly823Glu in Familial Hypertrophic Cardiomyopathy using a Mouse Model03:45

Investigating the Pathogenesis of MYH7 Mutation Gly823Glu in Familial Hypertrophic Cardiomyopathy using a Mouse Model

Published on: August 8, 2022

3.3K
Array Comparative Genomic Hybridization Array CGH for Detection of Genomic Copy Number Variants09:16

Array Comparative Genomic Hybridization Array CGH for Detection of Genomic Copy Number Variants

Published on: February 21, 2015

19.4K

Related Concept Videos

Comparing Copy Number Variations and SNPs02:26

Comparing Copy Number Variations and SNPs

Sequencing of the human genome has opened up several best-kept secrets of the genome. Scientists have identified thousands of genome variations that exist within a population. These variations can be a single nucleotide or a larger chromosomal variation.
Copy number variations or CNVs are the structural variations that cover more than 1kb of DNA sequence. The single nucleotide polymorphism (SNP), on the other hand, is a single nucleotide change or a point mutation that is found in more than 1%...
11.4K
Single Nucleotide Polymorphisms-SNPs01:05

Single Nucleotide Polymorphisms-SNPs

A single nucleotide polymorphism or SNP is a single nucleotide variation at a specific genomic position in a large population. It is the most prevalent type of sequence variation found in the human genome. Point mutations that occur in more than 1% of the population qualify as SNPs. These are present once every 1000 nucleotides on an average in the human genome. Replacement of a purine with another purine (A/G) or a pyrimidine with another pyrimidine (C/T) is known as a transition. In contrast,...
14.3K
Genome-wide Association Studies-GWAS01:11

Genome-wide Association Studies-GWAS

Genome-wide association studies or GWAS are used to identify whether common SNPs are associated with certain diseases. Suppose specific SNPs are more frequently observed in individuals with a particular disease than those without the disease. In that case, those SNPs are said to be associated with the disease. Chi-square analysis is performed to check the probability of the allele likely to be associated with the disease.
GWAS does not require the identification of the target gene involved in...
12.3K
Pleiotropy01:33

Pleiotropy

Pleiotropy is the phenomenon in which a single gene impacts multiple, seemingly unrelated phenotypic traits. For example, defects in the SOX10 gene cause Waardenburg Syndrome Type 4, or WS4, which can cause defects in pigmentation, hearing impairments, and an absence of intestinal contractions necessary for elimination. This diversity of phenotypes results from the expression pattern of SOX10 in early embryonic and fetal development. SOX10 is found in neural crest cells that form melanocytes,...
31.2K
Genetic Lingo01:11

Genetic Lingo

Overview
84.2K
Cancer-Critical Genes I: Proto-oncogenes01:33

Cancer-Critical Genes I: Proto-oncogenes

Genes usually encode proteins necessary for the proper functioning of a healthy cell. Mutations can often cause changes to the gene expression pattern, thereby altering the phenotype.
When the function of certain critical genes, especially those involved in cell cycle regulation and cell growth signaling cascades, gets disrupted, it upsets the cell cycle progression. Such cells with unchecked cell cycles start proliferating uncontrollably and eventually develop into tumors.
Such genes that act...
8.8K