mohammad medhi heidari phd, assistant professor of molecular genetics, department of biology,sciences school,yazd university of medical sciences, yazd,iran mehri khatami phd, assistant professor of molecular genetics, department of biology,sciences school,yazd university of medical sciences, yazd,iran massoud houshmand phd, assistant professor of human molecular genetics,department of medical genetic,national institute of genetic engineering and biotechnology,tehran,iran eisa mahmoudi phd, assitant professor of mathematical statistic,department of statistics,yazd university, yazd,iran shahriar nafissi md, associate professor of neurology, neurology department, tehran university of medical sciences, tehran,iran