Distortion of transmission ratio by a candidate t complex responder locus transgene.

The mouse t complex responder locus (Tcr) is centrally involved in the phenomenon of male-specific transmission ratio distortion (TRD) through its action in haploid germ cells. Previously, we identified a candidate gene, Tcp-10b, whose t allele generates alternatively spliced transcripts. The full-length Tcp-10bt transcript is present in pre- and postmeiotic germ cells and encodes a product that is virtually identical with that encoded by the wild-type allele. The alternatively spliced t-specific transcript is observed in post-meiotic haploid spermatids and would encode an altered polypeptide that could convey the Tcrt phenotype. To assess their function, we have introduced constructs representing each Tcp-10bt transcript into transgenic mice. Breeding experiments demonstrate that these two constructs alter the transmission ratios of t haplotypes from male mice, but in opposite directions. The results provide support for the hypothesis that Tcp-10bt is a component of the Tcr locus.