Anais Brasileiros de Dermatologia
On-line version ISSN 1806-4841
BROCHADO, Maria José Franco et al. Val247Leu polymorphism of β2 glycoprotein 1 gene may justify the genesis of anti β2GP1 antibodies and Antiphospholipid Syndrome in Multibacillary Leprosy. An. Bras. Dermatol. [online]. 2009, vol.84, n.4, pp. 355-359. ISSN 1806-4841. http://dx.doi.org/10.1590/S0365-05962009000400006.
BACKGROUND - Multibacillary (MB) leprosy may be manifested with antiphospholipid antibodies (aPL), among which anti-β2GP1 (β2-glycoprotein 1). High titers of aPL are associated with APS (Antiphospholipid Syndrome), characterized by thrombosis. The mutation Val247Leu in the domain V of β2GP1 exposes hidden epitopes with consequent development of anti-β2GP1 antibodies. OBJECTIVE: To evaluate the Val247Leu polymorphism of β2GP1 gene and its correlation with anti-β2GP1 antibodies in leprosy patients. METHODS: The Val247Leu polymorphism was performed by PCR-RFLP and anti-β2GP1 antibodies were measured by ELISA. RESULTS: The genotypic Val/Val was more prevalent in the leprosy group, compared to controls. Regarding the 7 MB patients with APS, four presented heterozygosis and three, Val/Val homozygosis. Although higher titrations of anti-β2GP1 IgM antibodies were seen in MB leprosy group with Val/Leu and Val/Val genotypes, there was no statistical difference when compared to Leu/Leu genotype. CONCLUSION: The prevalence of Val/Val homozygosis in leprosy group can partially justify the presence of anti-β2GP1 IgM antibodies in MB leprosy. The description of heterozygosis and Val/Val homozygosis in 7 patients with MB leprosy and thrombosis corroborates the implication of anomalous phenotype expression of β2GP1 and development of anti-β2GP1 antibodies, with consequent thrombosis and APS.
Keywords : Antibodies; antiphospholipid; beta 2-glycoprotein I; Leprosy; Polymorphism; genetic.