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The aim has been to set up a rapid and accurate microarray assay using sandwich mode for sex determination of bovine preimplantation embryos. Twelve sequence-specific oligonucleotide capture probes used to discriminate 12 samples were spotted onto the aldehyde-modified glass slides by Arrayer. The 2 recognition probes used to identify coding regions of the sex-determining region of the Y chromosome gene (SRY) and β-casein (CSN2) reference gene were coupled with biotin. The assay was optimized by using genomic DNA extracted from blood samples of known sex individuals. Polymerase chain reaction (PCR) was used to amplify the fragments in the HMG box region of SRY gene and CSN2 gene with sequence-specific primers. The sex of samples was identified by detecting both the SRY and CSN2 genes simultaneously in 2 reaction cells of microarrays, with the male having SRY and CSN2 signals and the female only CSN2. The sex of 20 bovine preimplantation embryos was determined by oligonucleotide microarray. The protocol was run with a blind test that showed a 100% (82/82) specificity and accuracy in sexing of leukocytes. The bovine embryos were transferred into 20 bovine recipients, with a pregnant rate of 40% (8/20). Three calves were born at term, and 5 fetuses were miscarried. Their sexes were fully in accordance with the embryonic sex predetermination predicted by oligonucleotide microarray. This suggests that the oligonucleotide microarray method of SRY gene analysis can be used in early sex prediction of bovine embryos in breeding programs.

Doppel protein (abbreviation Dpl) is a newly recognized Glycosyl phosphatidyl inositol (GPI) anchored and highly glycosylated protein, which is similar to prion protein (PrP) in the chemical structure. The encoding gene of Dpl named PRND locates at the downstream of the prion protein gene (PRNP). These two proteins are different in physiological functions. The expression of Dpl focuses on testis tissue at the adult, and takes an important role in maintaining sperm integrality, normal fertility, and motion ability. We reviewed the biological characters, physiological functions of Dpl and its effects on male reproduction in order to provide theory guidance for the study on physiological function and male reproduction controlling.

The plasmid DNA was purified using the Fractogel EMD TMAE (M) anion exchange media. The dynamic loading capacity of this media for plasmid DNA was 0.62 mg/mL. It was found that when the lysate of bacteria was incubated with either Triton X-114 or Triton X-100 before purification, the average content of endotoxin left in the purified plasmid DNA was 6.42 EU/mg or 9.50 EU/mg, respectively. These results were much lower than that without pre-incubation (67.82 EU/mg). The purification of plasmid DNA and the removal of endotoxin were achieved in one step using anion-exchange chromatography. This method is simple, fast and of low cost.

BMPR-IB gene increases ovulation rate and litter size as a major gene in Chinese Merino, because of 746 A to G mutation. The aim of this study was to make oligonucleotide chips to determine single nucleotide polymorphism (SNP) in BMPR-IB gene. The oligonucleotide chips were manufactured by using six sequence-specific oligonucleotide probes derived from polymorphic regions in the mutation and spotting the probes by microarrayer onto the aldehyde modified glass slides. The 746 A to G mutation was detected with ovine blood in reaction cells of chips. The results were identified by designed the Arraydoctor 2.0 software, in accordance with those of restriction fragment length polymorphisms (RFLP). The results showed the oligonucleotide chips are a parallel, accurate and effective way for screening prolificacy in molecular-assisted selection(MAS)of sheep.