Identification and characterization of a new allele for the beta subunit of follicle-stimulating hormone in Chinese pig breeds.

During evaluation of follicle-stimulating hormone-beta (FSHB) expression in anterior pituitary glands by an RNase protection assay (RPA), the expected fragment of 205 nucleotides at positions 759-963 was not detected in one boar that had moderate plasma and pituitary FSH concentrations. After subcloning and sequencing, mRNA from this boar lacked an 11-bp fragment (5'-CATTTGGAAAC-3') at nucleotide positions 807-817 of the 3'-untranslated region (3'-UTR, D allele). Wild-type FSHB (WT allele) was present in pituitary RNA and genomic DNA in both Meishan (MS) and White Composite (WC) pigs; whereas the D allele was present only in MS pigs (P < 0.01; 5/6 MS vs. 0/6 WC). Also, we found the D allele in five other Chinese breeds but absent in ten American Landrace, 11 Yorkshire and 17 Berkshire pigs. Additionally, the D allele had one silent nucleotide change in the coding region plus six, single nucleotide changes in the 3'-UTR.