Allelic Variants of Gene in Isolates from Patients with Ixodid Tick-Borne Borreliosis.

Protein P66 is one of the crucial virulence factors of , inducing the production of specific antibodies in patients with ixodid tick-borne borreliosis (ITBB). Various species of are characterized by genetic variability of the surface-exposed loop of P66. However, little is known about this variability in Here we describe the variability of the nucleotide sequences of gene locus in isolates of Analysis of nucleotide sequences of P66 in 27 isolates of from ITBB patients revealed three allelic variants of this gene. The alignment score of amino acid sequences in the isolates showed amino acid replacements in various positions confirming the presence of three allelic variants. Two of them are characteristic only for some isolates of of the Eurasian gene pool from various parts of the geographic ranges of from various samples. At least three allelic variants of have been identified, which have different amino acid expression, occur with different frequency in ITBB patients and, presumably, can have different effects on the course of the infection.