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desirable properties, the chief of which is the absence of tree-level flavor-changing neutral currents, thus allowing the SU (2)$_{R}$ breaking scale to be as low as experimentally allowed by collider data. This became known in the literature as the alternative left-right model (ALRM) [4]. Here we explore further consequences of the DLRM, coming from the SU (2)$_{R}$ sector. 

## II. MODEL 

Consider the gauge group SU (3)$_{C}$ × SU (2)$_{L}$ × SU (2)$_{R}$ × U (1) × S , where S is a global symmetry such that the breaking of SU (2)$_{R}$ × S will leave the combination L = S − T 3 R unbroken. This allows L to be a generalized lepton number which is conserved [1] in all interactions except those which are responsible for Majorana neutrino masses. The fermion content of the DLRM is given by 

<img src='content_image/350610.jpg'>

<img src='content_image/350609.jpg'>

<img src='content_image/350608.jpg'>

This basic structure was already known many years ago [5, 6] but without realizing that n is a scotino, i.e. a dark-matter fermion. 

The scalar sector of the DLRM consists of one bidoublet and two doublets: 

<img src='content_image/350607.jpg'>

as well as two triplets for making ν and n massive separately: 

<img src='content_image/350606.jpg'>

Their assignments under S are listed in Table I. 

The Yukawa terms allowed by S are then ψ$_{L}$ Φ ψ$_{R}$ , Q$_{L}$ ˜ Φ Q$_{R}$ , Q$_{L}$ Φ$_{L}$ d$_{R}$ , Q$_{R}$ Φ$_{R}$ h$_{L}$ , ψ$_{L}$ψ$_{L}$ Δ$_{L}$, and ψ$_{R}$ψ$_{R}$ Δ$_{R}$, whereas ψ$_{L}$ ˜ Φ ψ$_{R}$ , Q$_{L}$ Φ Q$_{R}$ , and h$_{L}$d$_{R}$ are forbidden. Hence m$_{e}$ , m$_{u}$ come from 

