New methods are required for more objective estimation of the polymorphic genes contribution in multifactorial diseases. We suggest new approach based on the calculation of relative "score" as a sum of relevant genetic polymorphisms studied. Application of suggested approach is evaluated in analysis of the genes REN (19-83G>A), AGT (M235T), ACE (I/D), AGTR1 (1166A>C), AGTR2 (3123C>A), BKR2 (-58T>C and I/D) in children with arterial hypertension. The method proved that polymorphism of renin-angiotensin and kinin-bradikynin gene systems renders essential influence on formation of stably raised arterial pressure in girls.