Here, for the first time, the structure of genes involved in sex determination in mammals (full
Sry and partial
Rspo1,
Eif2s3x, and
Eif2s3y) was analyzed for the European mole
Talpa europaea with ovotestes in females. We confirmed male-specificity for
Eif2s3y
[...] Read more.
Here, for the first time, the structure of genes involved in sex determination in mammals (full
Sry and partial
Rspo1,
Eif2s3x, and
Eif2s3y) was analyzed for the European mole
Talpa europaea with ovotestes in females. We confirmed male-specificity for
Eif2s3y and
Sry. Five exons were revealed for
Rspo1 and the deep similarity with the structure of this gene in
T. occidentalis was proved. The most intriguing result was obtained for the
Sry gene, which, in placental mammals, initiates male development. We described two exons for this canonically single-exon gene: the first (initial) exon is only 15 bp while the second exon includes 450 bp. The exons are divided by an extended intron of about 1894 bp, including the fragment of the LINE retroposon. Moreover, in chromatogram fragments, which correspond to intron and DNA areas, flanking both exons, we revealed double peaks, similar to heterozygous nucleotide sites of autosomal genes. This may indicate the existence of two or more copies of the
Sry gene. Proof of copies requires an additional in-depth study. We hypothesize that unusual structure and possible supernumerary copies of
Sry may be involved in ovotestes formation.
Full article
