MHC Region rs114771815: What Your Genotype Means
The genetic variant rs114771815 is a single-nucleotide polymorphism (SNP) located within the major histocompatibility complex (MHC) region on chromosome 6. Research has identified this variant as having a statistical association with idiopathic inflammatory myopathies, a group of rare autoimmune conditions characterized by muscle inflammation.
What each genotype means
Typical inflammatory risk profile
Your genotype carries two copies of the standard common C allele at this MHC locus. In genetic association studies, this genotype is not linked to elevated susceptibility to idiopathic inflammatory myopathies. It reflects the baseline population risk profile observed for this genomic marker.
Carried by approximately 80% to 90% of individuals of European ancestry and is the predominant genotype across most global populations.
Moderately altered myopathy risk
You carry one copy of the ancestral minor T allele associated with altered immune regulation within the major histocompatibility complex (MHC). Statistical studies indicate that carrying this allele is associated with an increased susceptibility to idiopathic inflammatory myopathies, including dermatomyositis and polymyositis. Because complex autoimmune conditions are polygenic and influenced by environmental triggers, having this variant does not indicate a diagnosis.
Carried by roughly 10% to 18% of people of European descent; it occurs at markedly lower frequencies in East Asian and African ancestries.
Elevated myopathy risk profile
You carry two copies of the minor T allele in the MHC region associated with idiopathic inflammatory myopathies. In cohort studies, carrying two risk alleles confers a stronger statistical correlation with autoimmune inflammatory myopathies compared to carrying one or none. However, many individuals with this genotype never develop an inflammatory muscle disorder, as overall risk depends on multiple genetic and environmental factors.
Found in less than 1% of individuals across most ancestries, occurring in approximately 0.5% to 1% of individuals of European descent.
Understanding the SNP and Its Location
The variant rs114771815 is a specific position in the human genome located within the major histocompatibility complex (MHC) region on the short arm of chromosome 6. This region is highly complex and plays a critical role in the immune system by helping the body distinguish between its own proteins and those from foreign invaders like viruses or bacteria. Because the MHC region is densely packed with genes involved in immune regulation, variations here are frequently studied in the context of autoimmune diseases. Scientists use genome-wide association studies (GWAS) to identify these specific markers, like rs114771815, to better understand the genetic architecture of complex health conditions. It is important to note that a SNP is simply a single-letter change in the DNA sequence and does not necessarily cause a disease on its own, but rather serves as a signpost for genetic patterns.
The Role of the MHC Region
The MHC region contains the human leukocyte antigen (HLA) genes, which are essential for the proper functioning of the immune system. These genes provide instructions for making proteins that sit on the surface of cells and present pieces of proteins to T-cells, which are specialized immune cells. When the immune system functions correctly, it uses these signals to identify and destroy infected or abnormal cells. However, in the context of idiopathic inflammatory myopathies, the immune system may become overactive or misdirected, leading to inflammation in muscle tissue. Because the MHC region is so central to immune surveillance, variations in this area are often investigated to see if they influence how the immune system recognizes self-tissues. While the MHC is the strongest genetic driver for these conditions, the biological mechanisms are intricate and involve many interacting genetic and environmental factors.
Research Associations and Evidence Strength
Scientific research, including large-scale genome-wide association studies, has identified rs114771815 as having a statistical association with idiopathic inflammatory myopathies. In studies of individuals of European ancestry, this variant has shown significant associations with various myositis phenotypes. While the statistical evidence is considered moderate to strong in the context of these specific studies, it is crucial to understand that these findings represent population-level correlations rather than individual predictions. Researchers have noted that while rs114771815 shows a significant signal, it is often found in linkage disequilibrium with other classic HLA alleles. This means the variant is frequently inherited alongside other genetic markers in the MHC region, making it difficult to determine if the variant itself is the functional cause or simply a marker for a nearby genetic factor. Consequently, the scientific community views this as a piece of a much larger, complex genetic puzzle.
What You Can and Cannot Do With This Information
Genetic information regarding variants like rs114771815 is intended for educational and research purposes. It is vital to understand that having a specific genotype for this variant does not mean an individual will develop an inflammatory myopathy. These conditions are rare and complex, involving a combination of genetic predisposition, environmental triggers, and other unknown factors. This information cannot be used to diagnose a medical condition, predict future health outcomes, or guide personal medical decisions. If you have concerns about muscle weakness, persistent inflammation, or autoimmune symptoms, you should consult a qualified healthcare professional or a rheumatologist. They are the only ones qualified to evaluate your clinical history, perform necessary diagnostic tests, and provide appropriate medical guidance. Never use genetic data to alter your lifestyle or medical care without professional supervision.
How common is this variant?
The minor allele frequency for rs114771815 is approximately 0.05 to 0.10 in populations of European descent. Frequencies may vary significantly across different global ancestral groups.
Frequently asked questions
What are idiopathic inflammatory myopathies?
Idiopathic inflammatory myopathies are a group of rare autoimmune diseases that cause chronic muscle inflammation and weakness. Common types include dermatomyositis, polymyositis, and inclusion body myositis.
Does having the rs114771815 variant mean I will get sick?
No. Genetic variants are only one part of a complex system. Most people with this variant will never develop an inflammatory myopathy, as these conditions are rare and require multiple factors to occur.
Is this variant a diagnostic test for myositis?
No, this is not a diagnostic test. Diagnosis of inflammatory myopathies is based on clinical symptoms, physical examinations, blood tests, and muscle biopsies performed by a doctor.
Why is the MHC region so important in genetics?
The MHC region contains genes that are essential for immune system function. Because it is so central to how the body identifies threats, it is a major focus for research into autoimmune and inflammatory diseases.
Sources & further reading
Educational information only, last refreshed 10/13/2026. Not medical advice — these associations describe population statistics, not individual predictions.
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This variant is located in the MHC region, which has been shown to contain multiple independent risk signals for idiopathic inflammatory myopathies.
This variant in the MHC region is associated with idiopathic inflammatory myopathies, with recent GWAS identifying new HLA associations in the MHC Class 1 region reaching genome-wide significance.
This variant is located within the MHC Class 1 region, which has been confirmed by recent large-scale GWAS to harbor significant risk loci for idiopathic inflammatory myopathies.
This variant is associated with the MHC Class 1 region, which recent research confirms is a critical site for genetic risk in idiopathic inflammatory myopathies.