Gender Determination by PCR Assay for The Sex-Determining Region Y(SRY) Gene Amplification in Linnaeus’s Two-Toed Sloth (Choloepus Didactylus)

Year 2023, Volume: 42 Issue: 1, 24 - 28, 01.07.2023

Sena Ardıclı , Berkay Bozkurt Ezgi Vatansever

https://doi.org/10.30782/jrvm.1283245

Abstract

In Linnaeus’s two-toed sloths (Choloepus didactylus), there is no distinct sexual dimorphism. It is an obstacle for gender determination from
the external genitalia, especially in newborns or young sloths. Hence, easy, rapid, and reliable genetics-based methods for gender identification
of the sloths are needed to continue captive breeding more successfully. In this study, a PCR-based technique that allows gender determination
of two-toed sloths by using a sex-determining region Y (SRY) gene marker was described. The hair samples from young (suspect
gender) and adult sloths (known gender) were used in genetic analysis. Initially, genomic DNA was isolated from hair root samples using
Roche high pure PCR template preparation kit. The SRY primers were specifically designed based on the NCBI and Ensembl databases, and
they were verified with the BLAST program concerning the two-toed sloth genome. PCR amplification with the SRY-specific primers was
carried out by a programmable thermal cycler device using FastStart High Fidelity PCR System, Roche dNTPack. The samples were then electrophoresed
on 2% agarose gels and were visualized by a gel documentation and analysis system. A specific band in the electrophoresis pattern
is diagnostic for a male individual with a partial SRY region. Hence, the analysis demonstrated that the samples belonged to a male two-toed
sloth. Two-toed sloth species are commonly preferred animals in zoos. Gender determination is inevitable for these animals in captivity to
be raised successfully and healthily. Molecular genetic techniques allow high efficiency in taxonomic evaluations and gender identification in
species that do not display sexual dimorphism. The PCR assay described here may be helpful for a rapid genetic analysis that can be widely
used in gender determination for two-toed sloths.

Keywords

Two-toed sloth, PCR, Sex identification, SRY gene

Thanks

The authors gratefully thank Faruk Yalçın Zoo for the support.

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