Males are preferred over females in breeding programs for certain working dogs, such as police dogs, as well as in research programs studying genetic disorders that almost exclusively affect males. This study investigated the presence of two proteins in dog sperm that have been found only in X-chromosome sperm in other species: these X-sperm fuse with the egg to make XX (female) embryos, with Y-chromosome sperm fusing to make XY (male) embryos. We evaluated whether these proteins could be targeted to increase the Y-chromosome sperm obtained for use in assisted conception in dogs. Overall, we found that whilst these proteins appear to be found in both X- and Y-chromosome dog sperm, their functionality appears to differ. Activating these proteins allowed us to effectively obtain Y-chromosome sperm without damaging them. This is the first successful report of a targeted, yet non-damaging, sperm sexing method in dogs and represents a promising tool for advancing research into currently incurable genetic diseases.
Shattock et al. (Tue,) studied this question.