  We use the left-right symmetry model based on SU(2)_{L}xSU(2)_{R}xU(1)_{B-L}
gauge group with two bidoublets and one doublet Higgs field for electroweak
interaction. The lepton fields are represented as a doublet of SU(2)for both
left and right fields. By using the pattern of symmetry breaking emerges as the
minimum of the Higgs potential for a range of parameters, we show that the
domination of the V-A over V+A interactions is natural at low energy. The
symmetry breaking is the responsible mechanism for the up-down lepton doublet
mass difference
