Indexes of similarity of profiles of DNA of Streptococcus mutans in binomials.

CARLETTO KÖRBER FPM, GONZÁLEZ ITTIG RE, JIMENEZ MG & CORNEJO LS

San Miguel de Tucumán, Argentina

Congreso; XXXVIII Reunión Anual de la Sociedad Argentina de Investigación Odontológica; 2006

Sociedad Argentina de Investigación Odontológica

The purpose of this investigation was to compare the coefficient of genetic homology of Streptococcus mutans in 24 binomials mother-child that converged to the University Hospital of Maternity and Neonatology of Córdoba, using of similarity indexes Simple Matching (SM), Jaccard (J) and Dice (D). Were used strains of Streptococcus mutans recovered of samples of saliva and dental plaque the binomials mother-child at the 18 months of the childs age. The bacterial colonies were harvested from a 5 ml brain heart infusion, broth culture inoculated with colony and incubated at 37ºC during 48 hs. The DNA extraction was carried out according by Bollet method. The AP-PCR was performed with primers OPA 05 and OPA 02, a thermocycler Biometra uno II Thermoblock, with 50 cycles. The products of AP-PCR were resolved by electrophoresis in gel of agarosa 1% (0,5(g/ml of ethidio bromide) The profiles of the samples were analyzed side by side visual comparison, assigned to each amplified band 1 (present) or 0 (absent). The score frequency with which it happens each one of these events when are compared two profiles molecular individual were denominated a (1-1), b (1-0), c (0-1) and d (0-0). The indexes of similarity SM, J and D were applied using the program Infostat P 1.5. The indexes SM, J and D applied to the profiles RAPD of the bacterial strains of Streptococcus mutans isolated of the binomials mother-child showed of coefficient of similarity that varied between 0,11 and 1. The strains were considered with genetic similarity when the value of the coefficient was 0,50. SM and J revealed genetic similarity in 47% of the binomials studied, while the index D evidenced genetic similarity in 64,7% of the same ones. The different results obtained of the application of the indexes SM, J and D, it is that the index D ponders differentially the coincidences of presence of bands (1-1) respect to the differences (1-0) and (0-1) of the profiles molecular individual analyzed.