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these unexpected departures in sex ratio are briefl y summarized by Pandian
(2011). PCR analysis has shown that the unexpected female progenies
sired by YY androgenics are indeed genetic males but function as female
phenotypes (e.g., Puntius conchonius , Kirankumar et al., 2003; Hemigrammus
caudovittatus , David and Pandian, 2006; Fig. 6). In O. latipes , a cross between
two strains namely (Y Awr Y Awr ) ♀ x Ol-vas (XY Hdr ) ♂ is also reported to produce
Ol-vas (Y Awr Y Hdr ) ♂ and Ol-vas (XY Awr ) ♀. But in the absence of Dmrt1b Y Hdr
expression, the cross produces genotypic and phenotypic females. In the
presence of Ol-vas genotype, a phenotypic hermaphrodite and in the
absence of it, phenotypic males are also generated, as shown by PCR
analysis (Herpin et al., 2007). Hence PCR analysis to identify genetic sex of
Fig. 6. Upper panel: PCR products of the genomic DNA of Hemigrammus caudovittatus as
amplifi ed by Dmrt1 primer. A row: Lane 1 = male, Lane 2 = female, Lanes 3-13 androgenic
males generated using fresh or cadaveric sperm. B row: Lanes 1-7 unexpected female progenies
and Lanes 8 and 9 male progenies (from David, 2004). Lower panel: Oryzias latipes progenies
sired by an Ol-vas XY Hdr ♂ crossed with Y Awr Y Awr female. Note the absence of Dmrt1bY Hdr
expression on genotypic and phenotypic females and also the absence of expression of Ol-
vas in genotypic and phenotypic females but its presence in males including a phenotypic
hermaphrodite (from Herpin et al., 2007)
Color image of this figure appears in the color plate section at the end of the topic.
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