Abstract
Background: Sarcoidosis is a multisystem disease characterized by noncaseating granuloma formation, mostly affecting the lung. A variant in the TNFRSF1A region has been found to codify a protein capable of TNF antagonism. This variant is also associated with the development of multiple sclerosis but is absent in autoimmune diseases highly responsive to TNF-alpha treatment.
Aim: To search for the presence of TNFRSF1A SNP in sarcoidosis patients and its potential correlation with disease phenotype.
Patients and method: 79 patients with histologically proven lung sarcoidosis (49 male, 30 female) and 50 healthy controls (HC) were studied. Radiological stage and organ involvement were assessed. DNA was extracted from peripheral blood and rs1800693 SNP was determined by PCR. Genotyping was performed by pyrosequencing. Correlation with stage and clinical profile of sarcoidosis was investigated.
Results: The alleles of rs1800693 SNP were in Hardy-Weinberg equilibrium in the studied subjects. The frequency of A/A genotype was 27%, A/G 54% and G/G 19% in sarcoidosis patients, similar to HC. The mean duration of disease was 4.9±3 years. No correlations were seen between genotype and age at onset, gender, serum ACE, organ involvement or use of corticosteroids. In patients with the G/G genotype, DLCO at diagnosis was significantly lower than in those with the A/G or A/A genotype (59±19 vs 73±11 and 79±11% pred, p=0.019) and duration of disease tended to be longer (6.1 vs 5.2 and 4.3 years, respectively).
Conclusion: The presence of the G allele of the rs1800693 SNP in sarcoidosis can be related to more severe lung functional impairment in sarcoidosis.
- Copyright ©ERS 2015