The mutton sheep and goat genetics and breeding team led by Professor Chu Mingxing from the Institute of Animal Sciences (IAS) of CAAS, reported that allele T of PROP1 gene is a potential marker for improving litter size in sheep. This study provides insights into the association between PROP1 gene and prolificacy in Small Tail Han sheep. The result of this study was published inJournal of Geneticson June 9, 2015.

Litter size is a favorable economic trait for the sheep industry, but remains a complex trait controlled by multiple genes in multiple organs. The Small Tail Han sheep is excellent local breeds in P. R. China, display significant characteristics of year-round estrus and high prolificacy.

The PROP1 gene was selected as a candidate gene for high prolificacy in some sheep breeds. Single nucleotide polymorphisms (SNPs) of all exons and part of intron of PROP1 gene were detected in Small Tail Han, Hu, White Suffolk and Texel sheep by PCR-RFLP. Three genotypes (CC, CT and TT) were detected in Small Tail Han, Hu and Texel sheep, and two genotypes (CC and CT) were detected in White Suffolk sheep. Sequencing revealed a C to T mutation at 330 position of intron 1 of PROP1 gene in TT compared with CC. The ewes with genotype TT or CT had 0.83 (P<0.05) or 0.47 (P<0.05) lambs more than those with genotype CC, and the difference of the litter size between TT and CT genotypes was not significant（P>0.05）in Small Tail Han sheep. These results preliminarily indicated that allele T of PROP1 gene is a potential marker for improving litter size in sheep.