B ▁found ▁in ▁this ▁stra in ▁is ▁inherited ▁through ▁gene ▁dup lication ▁and ▁ampl ification ▁between ▁gener ations , ▁and ▁even ▁self - fer til izations . ▁The ▁inheritance ▁of ▁this ▁alle le ▁is ▁the ▁first ▁description ▁of ▁gene ▁dup lication ▁and ▁ampl ification ▁in ▁the ▁mic ron uc le us ▁of ▁c ili ates . ▁Additionally , ▁it ▁appears ▁that ▁the ▁dup lication ▁of ▁the ▁mut ant ▁alle le ▁occurred ▁after ▁mut agen esis ▁due ▁to ▁the ▁similarity ▁in ▁nucle ot ide ▁sequences ▁of ▁different ▁copies ▁of ▁the ▁mut ant ▁alle le , ▁especially ▁in ▁the ▁coding ▁region . ▁When ▁the ▁d 4 - 9 5 ▁stra in ▁was ▁crossed ▁with ▁a ▁wild - type ▁P . ▁t etra ure lia , ▁F 2 ▁and ▁later ▁pro gen y ▁often ▁expressed ▁the ▁phen ot ype ▁of ▁the ▁pa wn - B ▁mut ant , ▁despite ▁carrying ▁a ▁wild - type ▁gene ▁at ▁the ▁pa wn - B ▁loc us . ▁This ▁phen ot ype ▁was ▁maintained ▁in ▁pro gen y ▁even ▁after ▁the ▁self - fer til ization ▁of ▁theoretical ▁wild - type ▁hom o zy g otes ▁that ▁had ▁been ▁recovered ▁from ▁the ▁cross . ▁▁▁ ▁As ▁is ▁the ▁case ▁of ▁other ▁Par ame ci um , ▁P . ▁t etra ure lia ▁exhib its ▁a ▁number ▁of ▁non - M end elian ▁modes ▁of ▁inheritance , ▁partially ▁due ▁to ▁the ▁existence ▁of ▁both ▁macro - ▁and ▁mic ron uc lei . ▁In ▁both ▁the ▁macro - ▁and ▁mic ron uc