LAUSR

Identifying the mechanism for sex determination in amphibians is challenging. Very little is known about sex determination mechanisms of Rana dybowskii, a species of importance to evolutionary and conservation biology. We screened for sex-linked molecular markers in R. dybowskii in China using target region amplification polymorphism (TRAP) with two fixed primers against the sequences of Dmrt1. We found two male-linked molecular markers in R. dybowskii, which were 222 bp and 261 bp long. The detection rates of 222bp marker in males form Xinglong, Huadian, and Dandong were 93.79%, 69.64% and 13.64%, respectively, while the rate in females from Huadian was 27.50%. Besides, the detection rates of 261bp marker in the above three regions were only observed in males at the rate of 93.79%, 87.50%, and 32.73%, respectively. The inheritance patterns of sex-linked molecular markers showed that the two sex-linked molecular markers were heterozygous. Compared to the XY-male parent, progeny from XX-pseudo-male parent possessed lower sex reversal ratio at the same rearing temperature, and the proportion of female froglets from an XX-pseudo-male parent was more than 95% at low rearing temperature (15°C). Our findings suggest that R. dybowskii displays male heterogamety, and the two sex-linked molecular markers may have a guiding significance for the protection and utilization of R. dybowskii. This article is protected by copyright. All rights reserved.