Genes encoding the and chains of follicle-stimulating hormone are not sites for the Booroola (FecB) mutation in sheep

Abstract

Bovine cDNA probes for the beta-subunit of follicle-stimulating hormone beta (FSH beta) and the alpha-subunit of the glycoprotein hormones identify genetic variation (polymorphic restriction fragments) near these genes in sheep. The inheritance of the polymorphic restriction fragments was studied in half-sibling pedigrees generated by mating heterozygous (B+) rams to non-carrier (++) ewes so that the co-inheritance or genetic linkage to the Booroola (FecB) locus and the alpha- and beta-subunits of FSH could be analysed. Genetic recombination was observed between the FSH beta locus and the FecB locus in all five families studied and between the alpha-subunit and the FecB locus in the two families studied. We conclude that the FecB mutation does not lie within the FSH beta- or alpha-subunit genes encoding the heterodimeric hormone FSH, and that the high concentrations of FSH observed in carrier ewes must result from indirect actions of the FecB mutation on the synthesis, processing, storage, release or metabolism of FSH.