Sexing single bovine blastomeres using TSPY gene amplification

Area of Science:

• Animal genetics
• Reproductive biology
• Molecular diagnostics

Background:

• The testis-specific protein Y-encoded (TSPY) gene is a Y-specific gene found in variable copy numbers across mammalian species, including cattle.
• Accurate sex determination of preimplantation embryos is crucial for livestock breeding and genetic management.

Purpose of the Study:

• To evaluate the effectiveness of the TSPY gene as a Y-specific marker for predicting preimplantation embryo sex in Nelore (Bos indicus) cattle.
• To assess the concordance of TSPY gene detection between single blastomeres and the remaining embryonic cells.

Main Methods:

• Nested PCR was employed to screen 36 single blastomeres and their matched 18 in vitro conceived embryos for TSPY gene amplification.
• Embryos were produced using sexed sperm to generate male embryos for validation.

Main Results:

• The results from single blastomeres and their corresponding remaining embryonic cells showed complete concordance.
• All 16 blastomeres from eight male embryos produced using sexed sperm tested TSPY-positive, confirming its male specificity.
• The high copy number of the TSPY gene likely enhances its utility as a marker.

Conclusions:

• The TSPY gene is a highly effective male-specific marker for sexing single cells in cattle embryos.
• This finding has significant implications for improving sex determination techniques in bovine reproduction.
• Future applications may involve integrating TSPY gene sequences into real-time PCR assays for faster and more efficient embryo sexing.