ys pl asia ▁is ▁an ▁inherited ▁aut os om al ▁re cess ive ▁dis order ▁due ▁to ▁a ▁mut ation ▁in ▁both ▁copies ▁of ▁the ▁T B X AS 1 ▁gene ▁on ▁chrom os ome ▁ 7 q 3 4 . ▁The ▁T B X AS 1 ▁gene ▁codes ▁for ▁the ▁en zym e ▁Th rom box ane - A ▁synth ase . ▁When ▁known ▁patients ▁with ▁the ▁disease ▁were ▁sequ enced ▁for ▁the ▁T B X AS 1 ▁gene ▁they ▁had ▁a ▁hom o zy g ous ▁miss ense ▁mut ation . ▁The ▁T B X AS 1 ▁gene ▁mainly ▁trans cri bes ▁in ▁cells ▁involved ▁with ▁the ▁ske let al ▁system ▁and ▁mus cular ▁system . ▁ ▁The ▁increased ▁b one ▁density ▁is ▁due ▁to ▁l ops ided ness ▁between ▁b ones ▁forming ▁and ▁b one ▁res or ption . ▁ ▁This ▁en zym e ▁has ▁a ▁couple ▁of ▁essential ▁functions ▁in ▁the ▁body ▁that , ▁if ▁removed , ▁could ▁lead ▁to ▁the ▁sympt oms ▁observed ▁with ▁the ▁disease . ▁Th rom box ane - A ▁synth ase ▁is ▁responsible ▁for ▁plate let ▁aggreg ation ▁and ▁the ▁reg ulation ▁of ▁b one ▁min eral ▁density . ▁Th rom box ane - A ▁synth ase ▁regul ates ▁b one ▁min eral ▁density ▁by ▁influen cing ▁the ▁two ▁gen es ▁T N FS F ₁ ₁ ▁and ▁T N FS F ₁ ₁ B , ▁which ▁encode ▁for ▁R AN K L ▁and ▁o ste oc last ogen esis ▁in hib itory ▁factor