Microchimerism in Behçet's disease

Behçet's disease (BD) is a multisystemic disorder of unknown etiology characterized by chronic relapsing oral aphthous lesions, genital ulcers, and uveitis. Immunological dysfunction is the most emphasized etiopathogenetic factor. Microchimerism is existence of an allogeneic DNA in a living creature. There are variable studies investigating the role of microchimerism on etiopathogenesis of autoimmune diseases. To our knowledge, no report has investigated the relationship between microchimerism and BD. We aimed to investigate the possible role of microchimerism on BD as an autoimmune disorder.

We analyzed the SRY gene as an indicator of fetal microchimerism in our patient and healthy control groups. The patients were 105 women with BD over 18 years old who had applied to multidisciplinary Behçet's disease clinic at Mersin University between 2005 and 2011. Patients were divided into two groups: group 1 consisted of 39 patients having a son, and group 2, 15 patients either nulliparous or having a daughter. Controls comprised two groups of women according to whether or not they had a son, i.e., group 3 (n = 51) and group 4 (n = 52), respectively. All patients with BD fulfilled International Study Group criteria for the diagnosis of BD.

Forty-one of 54 (75.9%) patients and four of 103 (3.9%) controls showed presence of the SRY gene. The difference between the patient and control groups was statistically significant (P < 0.001).

As a result of our study, microchimerism may be associated with the etiopathogenesis of BD. However, we think there is a need for a larger series of studies to support this hypothesis.