Abstract:
Approximately five to eight percent of domestic rams demonstrate a sexual attraction
towards other rams, directing no sexual behaviors towards estrous ewes. It has been
observed that these male-oriented rams (MORs) have a greater abundance of prolactin
mRNA than female-oriented rams in the medial preoptic area of the anterior
hypothalamus (MPOA-AH), a region critical for the expression of sexual behavior in
mammalian species. We hypothesize that this difference in prolactin expression may
arise from subtle differences in the transcriptional control sequences within the gene’s
promoter. While the ovine promoter sequence is not yet known, comparable regions in
the human demonstrate the presence of many direct and inverted repeated sequences.
Preliminary analysis of the sheep promoter region by bubble and inverted PCR, as well as
boomerang DNA amplification, has generated data consistent with inverted repeats.
Results generated by analysis using these DNA amplification techniques will be
described. In addition, future research aims regarding sequencing and further
characterization of the ovine promoter will be discussed.
