Is Sjögren's syndrome (SS) hereditary?

From the Guidelines

Sjögren's syndrome is not strictly hereditary, but it does have a genetic component, as suggested by the higher prevalence in women and familial occurrences, although the exact mechanism is not fully understood 1. The relationship between genetics and Sjögren's syndrome is complex, with certain genes increasing the risk of developing the disease, but not guaranteeing its onset. Key factors to consider include:

• Genetic predisposition: Family members of people with Sjögren's have a higher chance of developing the condition or other autoimmune disorders, indicating a genetic component 1.
• Environmental triggers: Viral infections, hormones, and other triggers likely play important roles in causing the disease to develop, in addition to genetic susceptibility.
• Autoimmune nature: The complex interplay between genetic susceptibility and environmental triggers is typical of autoimmune diseases, such as Sjögren's syndrome. Some important points to note about Sjögren's syndrome include:
• Prevalence: Approximately 0.4% of the population is affected, with a female-to-male ratio of 20:1 1.
• Diagnosis: Defined, objective criteria for diagnosing and classifying Sjögren's syndrome have been proposed, including anti-SSA/Ro antibody positivity and focal lymphocytic sialadenitis 1.
• Treatment: Topical lubricants, topical anti-inflammatory therapy, and tear-conserving strategies seem effective in managing dry eye secondary to Sjögren's syndrome, although more research is needed to support therapy recommendations 1.

From the Research

Genetic Component of Sjögren's Syndrome

• The genetic basis of Sjögren's syndrome is not fully understood, but research suggests that there is a genetic component to the disease 2.
• Studies have shown that the prevalence of primary Sjögren's syndrome in siblings is estimated to be 0.09%, which is slightly lower than the general prevalence of the disease 2.
• The observed aggregation of autoimmune diseases in families of patients with primary Sjögren's syndrome supports the idea of a genetic component in its etiology 2.
• Specific genetic associations have been identified, including ancestral haplotype 8.1 and TNF, IL10, and SSA1 loci, although these are not specific to Sjögren's syndrome 2.

Current State of Genetic Research

• Despite the evidence for a genetic component, the pathogenesis of Sjögren's syndrome has not been fully elucidated, and only a few genes have been identified as associated with the disease 3.
• These associated genes have only a weak or moderate effect, and larger multicenter studies are needed to provide more meaningful associations 3.
• Recent work has successfully established associations that shed light on the pathophysiology of Sjögren's syndrome and implicate aberrant innate and adaptive immune responses 4.

Need for Further Research

• Genetic studies on Sjögren's syndrome are still in their infancy compared to other autoimmune diseases, and more research is needed to understand the fundamental causes of the disease 4.
• Large international and collaborative studies are necessary to assess the genetics of Sjögren's syndrome and to identify new opportunities for improving clinical care 2, 3, 4.