Sex selection techniques and their implications

Abstract

Abstract Sex selection techniques provide economic benefits to dairy and beef herd management. Therefore, the development of such techniques has attracted the attention of reproductive biologists. There have been numerous studies concerning the development of sex selection techniques. As the sex of the offspring is determined by certain chromosomes, namely the X and Y chromosomes in mammals, most studies have focused on sperm sexing, attempting to separate the X and Y chromosome-bearing sperm based on differences in deoxyribonucleic acid (DNA) content, head size/volume, motility, and immunological specificity. However, most of these methods have failed to show reproducibility. Only the flow cytometric method has been confirmed to be accurate and reliable thus far. More than three decades have passed since this technique was first developed. The sexed semen produced with the method is currently commercialized and widely used for artificial insemination (AI) in cattle around the world. Recently, however, another technique based on differences in DNA contents using a fluidics device was developed by a commercial company. Studies focused on immunological approaches and the modification of sperm motility have also described the successful separation of the two types of sperm. Therefore, the present review evaluated the available sex selection techniques and their implications.