kou dis ' ▁experience ▁was ▁followed ▁in ▁ 1 9 7 5 ▁by ▁a ▁further ▁publication ▁in ▁Gut ▁magazine ▁that ▁included ▁spir al ▁b acter ia ▁living ▁on ▁the ▁borders ▁of ▁du od onal ▁ul cers . ▁The ▁medical ▁significance ▁of ▁Ste er ' s ▁find ings ▁was ▁dis reg arded , ▁but ▁he ▁“ cont in ued ▁to ▁publish ▁papers ▁on ▁H . ▁P yl ori , ▁mostly ▁as ▁a ▁h ob by ." ▁ ▁H . ▁p yl ori ▁can ▁inf ect ▁the ▁st om ach ▁of ▁some ▁people ▁without ▁causing ▁st om ach ▁ul cers . ▁In ▁investig ating ▁asympt om atic ▁carri ers ▁of ▁H . ▁p yl ori , ▁research ers ▁identified ▁a ▁gen etic ▁trait ▁called ▁Inter le u ik - 1 ▁beta - 3 1 ▁which ▁causes ▁increased ▁production ▁of ▁st om ach ▁acid , ▁resulting ▁in ▁ul cers ▁if ▁patients ▁become ▁inf ected ▁with ▁H . ▁p yl ori . ▁Pat ients ▁without ▁the ▁trait ▁do ▁not ▁develop ▁st om ach ▁ul cers ▁in ▁response ▁to ▁H . ▁p yl ori ▁in fection , ▁but ▁instead ▁have ▁increased ▁risk ▁from ▁st om ach ▁cancer ▁if ▁they ▁become ▁inf ected . ▁Investig ation ▁into ▁other ▁g astro int est inal ▁in fe ctions ▁has ▁also ▁shown ▁that ▁the ▁sympt oms ▁are ▁the ▁result ▁of ▁interaction ▁between ▁the ▁in fection ▁and ▁specific ▁gen etic ▁mut ations ▁in ▁the ▁host . ▁ ▁Path ogen ic ▁variants ▁of ▁E scher ich ia ▁col i ▁( 1 9 4 7