a b s t r a c t
The insulin-like growth factor 1 receptor (IGF1R) is a membrane glycoprotein mediating
most biological actions of IGF1 and IGF2, and has an important effect on ovulation, preimplantation
embryo development and pregnancy rate. The objectives of this study were
to detect IGF1R gene polymorphisms of cattle and analyze the relationship with superovulation
performance and pregnancy rates after embryo transfer (ET), as well as the hormone
concentrations at the day of ET. One reported SNP of IGF1R G404T and a novel SNP of IGF1R
G399A were analyzed in 170 Chinese Holstein donor cows and 118 Luxi recipients cattle.
Statistical analysis revealed that the G404T mutation was associated (p = 0.019) with
increased ovulation rate and females with this mutation had enhanced performance in producing
transferable embryos. For the polymorphic locus G399A, recipients with g.399 GG
and g.399 GA genotypes had greater pregnancy rates after ET than that of g.399 AA genotype.
Furthermore, the same tendency was observed that the genotype groups with greater
pregnancy rates had greater progesterone and lesser estrogen concentrations, but these
did not reach statistical significance. Results of the present study showed, for the first time,
that the polymorphism in IGF1R is associated with superovulation traits, and indicated that
the IGFIR gene can be used as a potential marker for donor selection